SOSSInvisible Hinge Model 216, 20 Minute Fire Rated, Zinc, Satin Brass Exterior Finish, Model Number 216US4, #14 x 1-1/2"

These hinges and the jig that you can purchase are very well made. I highly recommend

This is my second exercise with these hinges. In both cases, I did the tricky pockets by hand. In hindsight, I should have:a) Lay out pilot holes and outline from hinge and dimensions. The paper template is a tad off.b) Use an undersize Forster bit for drilling pockets, and be conservative routing pocket interior.c) Dremel tool with 1/2" sanding drum is a precise way to fine-tune pocket walls to clear hinges.In the end, I got a usable result after way too much time woodworking. I like the clean look for my specialty closets and the hinges have just enough friction to give a nice feel without feeling sticky. (I have three hinges per door, and the doors are relatively light.) If I could reboot the projects, I would still use these hinges. For the one-door/three hinge, I would follow my suggestions above. For the two (split) door/twelve hinges, I probably buy the SASS routing template.

I've used Soss hinges several times over the years, as they are just the ultimate in hidden hinges. Strong, durable, and dependable.

Product was an "open box" purchase. Boxes were sort of dirty, but the contents were in great shape. I'd never used this type of hinge before, but with well-alligned​ mortising the heavy door I was mounting (alone) slipped right into place. Hinges are invisible and strong, just as advertised.

worked like a charm