These hinges came from a factory that use to make wooden chicken coops. I've already sold several hundred on here and still have plenty more (thousands) to sell. I use them all the time on coop and pen doors. They are off set and can be used that way or are easily flattened out with a hammer. I usually flatten them out, depending on the project I'm working on. They are made of steel and are 4" long. I'm selling them for $15.00 for 30 of them postage included. I accept paypal/money order.