M3.75PF tool is quite REAL and offer a fast way to shoot a HOOK...via the use of a simple One Legged Staple...so that materials can be HUNG during drying cycles as they go down a conveyor line, for example. It leaves about 2-3/8" of the staple leg exposed for a nice long HOOK to easily hang materials on and which has myriad uses in production woodworking environments. The PF1 special order variety does the same thing, but shoots the staple's Main... Leg...down deeper so that about 2" are left standing proud. A shorter hook is the result but also more robust for heavier items to hang upon.