I would recommend these instead for boofing:

https://www.amazon.com/gp/product/B07PS2MDJQ

It’s much much more simple. Break the RDT in half, take the plunger out out of the injector, put the RDT in the tube, add a little water, shake then let the gas out, reinsert the plunger, tilt the injector upwards while pushing out any air with the plunger, apply lube, insert the injector in your rectum, and push the plunger.