Espresso knock box, optional TPU protector

Knock box for espresso portafilters. The examples printed are predominantly black model at 100% size, predominantly white model at 80%. I also designed a cover that can be printed in TPU to help protect the striking area. I printed one for the smaller model, but think it works just fine without it so I did not bother printing it for the full size but I included it in case anyone wanted to use it too.