ZMR 250 Uni-Spacer with Air-Slots (30mm High 4mm Arms)

Edited 3mm 15mm ZMR 250 Uni-Spacer with Air-Slots by Chr1s .(https://www.thingiverse.com/thing:916537). Thanks so much for this design!

Stretched design to 25mm and added a front bubble to support room for a receiver.
Note: this is Perfect Fit for 4mm arms