This is brand new ONE Heavy Duty Hinge - 4" x 7" x 1/8" thick, 304 Stainless Steel, part number 2600286 .  The hinge is black with a heavy finish, but I am not sure if it is painted or powder coat. One side of the hinge has 7/16" holes with 4" center, other side has 1/2" x 1 1/4" slotted holes with 3" center.

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