Guy Sie offers there Leica ISO film speed hot-shoe covers on thingiverse.com:
“On my fully manual ’50s Leica M3 rangefinder camera, the ISO film speed indicator dial on the back only goes up to 200 – the fastest speed available at the time. With film speeds going up to ISO 3200 now the dial is basically useless so I don’t bother with it, but then I have to remember what film I loaded last time I used the camera – which might be weeks ago. So, was it Delta 3200? Was it T-Max 100? Or maybe Neopan 400? Oops.
The hotshoe covers should be fairly universal, so you don’t have to own a Leica to use them. Give it a try. This set contains speeds 100, 125, 160, 200, 320, 400, 800, 1600 and 3200.”
