Original design by Aleksei Aliapkin / Gavitka (cloned to printables by vilerage, see remixed model for more details):

https://cad.onshape.com/documents/c19bb66f73c46cf9e94162c5/w/ea313e0d2af07d19b1dbf5f7/e/16c68bdc248833ce1dad9c60 

My modifications:

https://cad.onshape.com/documents/3fca5b4d766e342dd9ad5d17/w/ed766177a2c9a0400e81de14/e/0a725f389c4848caad7eb84f?renderMode=0&uiState=6776ea771d0f243c52a02d27