I believe this fan is an original GM 3770529 5 blade cooling fan for a 1964-1967 CHEVROLET CORVETTE 327 NON AC car. It has \"Front\" and \"H\" stamped on the front side but no other letters or numbers anywhere else. It has round head rivets on the front side and they are flattened on backside. 3\" across bolt holes, about 17 1/2 \" in diameter and center hole is 2 3/8\". Might fit other GM cars but because I can not find a stamped part number I can not guarantee what it originally came on. Please do your homework before you offer and make sure this fan will fit your application. Fan is straight and in very good condition.