This part lets you use M4 or M16 hi-cap or mid-cap magazines with your KWA M93R. HPA tapping your M93R is recommended to make use of the extra magazine capacity. You will need an M4 or M16 magazine latch to use this part and a generic screw you can find at a local hardware store. Note that due to the tolerances of 3D printing, some modification may be required.
Download the .stl here: https://www.thingiverse.com/thing:2440035
Video explanation here:
https://youtu.be/7QWL446en10