It's a hinge. It's stainless steel. I like that they came with the tiny screws, i used rivets for my application though. They have the smaller pin whichmakes them less bulky.
This last time i purchased it, the product is now different. Very very light duty, not strong at all.
My only complaint is that 6 out of the 30 pack had hinges that were stuck and wouldn't open. Well packaged, good quality. Very impressed and would absolutely buy again. Highly recommend this product.
The quality of these hinges is extremely poor. Wd40 or silicone lubricants only quiet the cracking and grinding for a week or less. Do not waste your time, both the home depot and lowe's have better quality product.