CKMTA12 '12V' On-Board Twin High Performance Air Compressor, Ideal for Air Lockers Locking Differentials, Tire Inflator, Air Horn, Air Tools and Pneumatic Tools.

I purchased this compressor to mount under the hood of my Chevy Colorado. I ordered the compressor and was surprised to have it the next day. I had used the free shipping that stated 5-8 days. I was very surprised. I opened the box to find the compressor and parts to be in excellent condition. The box contained everything needed for installation. It even had ring terminals and connectors to wire the harness to the battery. I was very happy with the wiring harness as well. The harness that is supplied with the compressor is designed for lockers, but I am using this compressor for tire fills. The harness was labeled very well and instructions were clear. I had no trouble with the wiring harness. The harness is plug and play. ARB even leaves one plug disconnected so only a small hole has to be drilled to get the switch to the cab area. I simply taped off the wires that I was not using. The wiring had a nice looking switch that is designed to be recessed in a small cut out. I found the switch to be good. The location I mounted the compressor was very tight, but the mount is made to pivot. I was unaware that the compressor body and manifold tube can also be rotated to facilitate various mounting locations. The compressor itself was heavier that I expected, but that was great. The compressor feels well made. I mounted the compressor and made the appropriate wiring connections under the hood. I actually mounted the switch under the hood as well. I used a small plastic gang box used in home wiring and used a Dremel Tool to route out a hole for the switch. I then used a metal plate to cover the box. I was then ready to use the compressor for the first time. I hit the switch and the compressor fired right up. The compressor only ran for about two seconds and shut down. The compressor comes with a pressure switch that shuts down the unit at around 90-100psi. The manifold tube is very small and it gets to that pressure very quick. The manifold tube also has a built in pressure safety relief valve just in case the pressure switch fails. I am not sure what pressure is required to permit the safety valve to operate. I had to source my own fittings to use the compressor as a tire fill unit. I did not purchase the kit offered by ARB because I can build it cheaper myself. I spent an additional $15.00 to make a manifold for my tire fill kit. I had to buy several pieces due to my mounting location under the hood. I also suggest to anyone that purchases the ARB tire fill kit to buy some Teflon tape. I completed the procedure and was ready to fill a tire. It should be noted that I already had 50 feet of 3/8 air hose and fitting to use the compressor. I wanted enough hose to reach from the engine bay to the tires on my travel trailer without uncoupling the trailer. I had been carrying a portable air tank in my truck that holds 120 psi. I decided to test the compressor by filling it up. I turned on the switch and watched the hose fill with air. The compressor then promptly shut off as designed. I filled my air tank from approx 40 psi to 90psi in approx 1 1/2 to 2 minutes. The compressor stopped filling at 90 psi. I was still impressed at the speed given the size of the compressor. I filled a car tire from 10 psi to 32 psi the next day and was equally impressed at the compressor. I think it was a wise investment and would buy it again if I had to go back. My installation took my friend and I two hours to complete. I had a small area to work with and had to "build" some tools to install some small screws in a tight place. I think my installation time was long, but I had a unique mounting location. Anyone with basic skills could install this compressor easily. I needed to drill three holes. The mounting plate has four holes, but I didn't use one due to mounting location restrictions. This is a good compressor and I hope to use it for many years. Good luck.

I have a 1998 Cherokee that has had an air locker of some sort since about 2000. For many years I had a Quick Air II compressor which served me well but not perfectly. I had several issues with it over the years. It finally quit completely about 6 years ago. After that I installed an on-board air compressor driven by the engine. This too turned out to have issues and I abandoned it. After that I returned to an electric compressor and bought a small Harbor Freight compressor just to run the lockers (all of my other setups were used for airing up and the lockers.) The Harbor Freight compressor turned out to be nothing but problems. Obviously you get what you pay for. The first one broke the pin on the crankshaft. I modified the compressor to use a bolt in the crankshaft and that fixed the problem. Then I had problems with it over heating. Finally one of the reed valves on the piston broke. I mention all of this to highlight all of the problems I've had over the years with something that is dead simple. I finally decided to quit messing around with junk and go with a compressor made by a company who specializes in air lockers and also has years of experience and a great reputation. Looking at the price of this tiny little guy I though it was very pricey for what I was getting. At the end of the day though, I've spent much more on unreliable and frustrating solutions. One major benefit, in addition to quality and reliability, is the fact that it is already set up to accommodate two solenoids and a pressure switch. I also believe you can get an air up kit for it if you'd like. I decided not to run an air gauge as I didn't feel I need one but I believe it will also accommodate one if you would like. In addition it includes wiring harnesses to connect everything. I cannot comment on whether they worked or not because everything was already wired by me from my past setups so there was no need to read invent the wheel. One thing I'd like to say is I don't think I would recommend the air up kit for this compressor. Not to use for airing up tires any way. If you were to use it for airing up balls and small items, maybe, otherwise get a larger portable compressor for airing up. Harbor Freight does make a larger portable compressor that looks suspiciously like a Viair and works quite well. All of this said, this is a great little compressor for running your air lockers. It airs up quickly and has plenty of capacity for this job. It is very compact which makes finding a place to mount it that much easier. After years of messing around with my air source on every wheeling trip it was nice to have a system that just plain worked and needed zero intervention! The price for this little guy may seem a bit high but in reality it is worth every penny.

Excellent product a complete package easy installation works great excellent quality

The purchase experience with Amazon was typically Amazon perfect; ARB tech 'support' not so much. I purchased the CMK12 to use as a mounted air supply in a R1100GS opting not to get the inflation 'kit' that is offered as the unit is the same and it includes about $100.00 usd for stuff I already had. Getting through to the very very very nice person at ARB was quick and easy-credit where credit is due-however the Company bailed on providing assistance for wiring the compressor which I really do understand but also would not provide a wiring diagram for the kit version stating that none is/was available ????????????? Bottom line is that I was on my own and most probably anyone else who opts to try this also. I was able to confirm that the tappings on the mini air receiver are 1/8" inch BSPP however I found out the hard way that apparently all BSPP to npt fittings are not the same as the two I got from a supply house we do business with did not fit, or rather would not fully thread in to contact/compress the gasket or washer-didn't really need to mount the gauge and pop valve there anyway. After two full days the install was complete and the performance really makes the ordeal worth it: time to fill the front tire, 110-80-19 from 0 to 36 psi approx 26 seconds and the rear tire , 150-70-17 from 0-42psi just under one minute-please note the bike was on the center stand. The engine was off and the bike started normally but of course I would opt to run the engine in the event we have to make a repair-cannot give the current draw as the meters I have read only dc micro/milliA. Cannot imagine anyone not being more than completely satisfied with the ARB compressor. For what it is worth; the only info on the compressor is ARB no country of origin no specs at all the box does state 'made in Australia' but can't help but to wonder if this means the box, the contents or both. Decided to get a meter which reads dc amps and raised the pressure of an unmounted 205 75 R14 trailer tire from 0 psig to about 36 psig, in roughly a minute and 30 seconds. Inrush just under 25A, less than 26A for about 45 seconds and remained under 27A for the duration. Could barely hold my hand on the cylinder head for a second, after 15 seconds the head was only warm BUT the ambient temp was 41*F, dew point 11*F. Hope this helps all considering getting one of these remarkable compressors.

Excellent 12v air compressor. I'm so impressed with it that I would never buy a different one, except maybe the twin version. This one has been so useful! I use it to air up tires at the end of a trail, blow dust off of gear, and inflate my air mattress. I've had mine installed and working for over a year now. Install was a breeze thanks to the unique mounting system. I have mine mounted inside a small hard case that I mounted in the back of my 2005 Frontier. My only complaint was the instructions, which assume you're using it to power ARB's air lockers. The supplied wiring and hardware is great, but I had already installed a relay block and auxiliary fuse box, so I had to figure out how to make the compressor work with my pre-installed wiring. Overall though, the install was very smooth and pretty easy. The design of the compressor is fantastic and feels very solid. I would not ever worry about how long it would last. Performance out of it has been nothing short of outstanding. It's filled up my tires as well as many friend's tires at the ends of countless off road adventures and has yet to have an issue. It does get warm but never overheats, even after very prolonged use. I can fill my 285/75R16s from 20 PSI to 42 PSI in about 2 minutes per tire, which is great. It has limited use with a blower nozzle, but that's just because I don't have a tank rigged up to it. For my purposes though, it's good enough without the tank. Overall, I can't recommend highly enough. It's become one of my main essentials now.

Compressor works great! Not too loud, fills up tires quickly after a day on the trails. Also great peace of mind for road trips combined with having plugs and a repair kit with you. Lots of wiring involved with installation, if you are comfortable with installing stereos/soldering/pulling wires then diy it. It is not for the novice installer and I can imagine a shop would be expensive to have installed. It took me several hours to run all the wires to the fuse box and battery/aux switches. I used a separately sold mount for the cargo area of my jeep which I would recommend if putting into a JL unlimited. The inflation kit sold separately is also a good value in my opinion but not included when you buy the compressor. Overall I'm very pleased with the performance of the ARB twin compressor. It suits my needs for airing up after trails and also I'm able to air up various things when I am not near my home compressor (pool floats, stuff like that). I have electronic lockers so I can't comment on their use for air lockers but as a compressor I've aired up 2 sets of 33 inch tires (8 total tires in one go) and it ran like a champ without hesitation. A+ product, hope it lasts!

When I purchased this ARB single, I found it here at the cheapest price at that time. Mounted under the hood, it's nice not to carry the heavy, fairly large portable pump I carried for years. Runs like you'd expect from an ARB product.

I purchased this air compressor because of the company reputation and many good reviews. Let me start by saying that the quality of this compressor is very good. I don't expect any performance issues with it and I love the small compact package this offers. Now I want to dive into some of the deficiencies that many people didn't mention and that you should know before you make this purchase. Watch some installation videos on this, then understand that those videos don't tell you that this is an all day or maybe even all weekend install like it was for me. It all seemed pretty straight forward however some details brought my install to a halt even though I consider myself a very capable mechanic. So block off a good chunk of time to do this installation. Buy your own air fittings from the hardware store. I purchased ARB's actual quick connect accessory kit thinking it would streamline the installation. It was a joke. I spend 46 bucks on a kit that I couldn't use. Why? Because 2 of the 3 air ports on the compressor are different and none of the fittings in the accessory kit allowed me to actually connect the quick connect fitting. Just go to the hardware store and buy yourself a regular air hose quick connect fitting and a 1/4 inch T fitting. Unless you have lockers don't plan on being able to use the two blocked off ports on the air chamber on the pump. I'll be returning the accessory kit. While the included wire harness is in fact pretty plug and play its very over complicated. ARB gives you a harness that controls the pump and the option for two locker switches. Most people aren't using lockers. In order to make everything work you have to use the whole wire harness even if you aren't running lockers. I ended up cutting off all of the unnecessary wires for the two extra switches because I didn't want to have to try and conceal a bunch of wires not being used. I'm a electronics technician by trade and they could have made this harness much more streamlined. Thank goodness for the mounting adjustments. I was able to tuck this pump in a very small area and the ability to rotate the pump and air chamber really helped get it right where I needed it. Once everything was hooked up and powered the air compressor works well. I have not yet used it to completely fill 4 tires but I don't have any doubt it will do the job.