6-Pack Invisible Concealed Cross Hinges Folding Table Cabinet Door Hinge Connection (Thick)

These are a nice inexpensive substitute for the Soss brand hinges. They are, however, not quite the same quality. They seem to be a little loose in the joints. Making them a little sloppy opening and closing. That being said they are still very functional. How long lasting they might be... Only time will tell. They are substantially less expensive, though, if price is an issue. Also be aware that they are not 3/8" they are actually 15/32" so if you are looking for a nice tight fit you will need a 15/32" bit for your router.