Made for the Pentax ME and the later Pentax ME Super.
But this also works on ME-F, MG, MV-1, Super A, SuperProgram, Program A, Program Plus, P5 and P50.

This is a nice and study winder which allows auto winding and can takes up to 2 frames per second.
It supports a cabled remote release and can be used in single or continuous modes.
Great build quality but it's noisy and quiet heavy.
Powered by 4 AA batteries and that of course adds a bit to the weight.
And the weight without batteries are 270g.
The grip is a little on the small size and can be a little cramped for this with a little bigger hands.
Battery life is also not all that great.

But still a great accessory if you want to use your old Pentax in situations when a bit more speed is needed.