These surplus latches are sold in various sizes. The model numbers may be the same but the depth range may be different from piece to piece.
The Hartwell is a unique spring loaded, trigger action latch, for cowling and access doors. Made of corrosion resistant steel. Rivet or spot weld to structure. Mounting plate is 2-1/8″ x 1-3/8″. Latch extends 1/2″ beyond plate.