SmaringWing DIY Tracked Robot Chassis Smart Tank Car Chassis Kit with 2pcs Motor, Caterpillar Moving Robotic Tank Platform with Plastic Tracks for Arduino Raspberry Pie Microbit Python Steam (Blue)

As far as I can tell, the "bearing wheels" or "idlers wheels" aren't actually meant to rotate. Any attempt to make these wheels spin-able will likely be met with problems. The rest of the chasis is pretty accurately what you see, a little too small to mount a battery, arduino, and L298N driver... but do-able. I ended up mounting a lexan plate on standoffs to make room for the parts. But you can kinda see it's small by the info. My main complaint is that idler wheel.

Been running on 3S 4500 and 4S 2200 Lipos, using L298 motor driver I and am enjoying the toying/testing on carpet. The motors have not gotten hot, only slightly warm thus far. Considering plugging in a 6S and checking/monitoring heat levels. Pay attention to instructions regarding removing track sections, the track pin is made to be removed from one direction only, and there is a brass tool in kit that works great. I needed to disassemble multiple times to figure out that I should have inspected better prior to initial assembly because there lacks details in assembly instructions. The hole in frame which the hex-head shaft is mounted is much larger than I would have expected and this caused confusion. I believe the "bearing shaft" should be held with nuts and washers through the hole that is large otherwise the tracks will not align vertically/horizontally depending. First assembly I mounted hex-head shaft in wrong location/hole through frame which caused the tracks to not extend the front and rear of frame evenly/symmetrically. Second assembly I again used incorrect mounting location/hole through frame and the track were not vertically symmetric/even. (I think the tracks were symmetric/even front to back but not up and down, I think cannot recall exactly).

Been running this guy on a 6S 1100mah drone racing lipo and Sabertooth 2x12 and Its a rocket ship. Im actually surprised how long it has lasted. Its alot of fun and very durable too.