This is a remix of the Mechanical Tally Counter 5.0 by FredrikHamrebjorkDesigns.

I modified the Left and Right buttons, and the Back Cover. All other parts can be printed downloaded from the original model maker's page: Mechanical Tally Counter 5.0 by FredrikHamrebjorkDesigns | Download free STL model | Printables.com

I recommend printing this model at 100% infill with 3 perimeters. I found it makes it stronger.

There is a detailed section of the remix below, but I am copying it here to make it easier to find:

Differences of the remix compared to the original

Left and Right Buttons:

• I widened them so they are a more exact fit. The result is smoother and more vertical motion up and down.
• I also extended the inside vertical wall down toward the bottom by a small amount. This keeps the button arms more precisely perpendicular, in a position that makes the button clicks more effective, consistent, and smooth.

Back Cover:

• The back cover comes integrated with the set screw to keep the front and back secured together. That screw broke several times on me while using the tally counter for various things. That forced me to reprint several times. I decided to enlarge the screw's diameter to make it stronger. I recommend printing the back cover at 100% infill with 3 perimeters, so the screw is the strongest it can be.

For anyone looking for that extra, super slick operation: a dab of white lithium grease on the internal friction points helps a bit :)