1 1/4 inch pipe -> US garden hose connector

thingiverse

Fits the inside of a 1 1/4 inch PVC pipe to a US garden hose. Use some plumbers tape! v2 has a wider center diameter. I've found you don't need quite so much strength for it to work. I've also found that printing in TPU is very effective for this part, and helps it fit a pipe snugly with a little force. Some hose connectors will reach the end when you twist them on and then have a "give" and disconnect, twist the hose on until you feel its tight and if it snaps out, just tighten it again but not so tight it comes loose again.