Made these for a softer landing option for the Peon230 although they would probably work for similar sized drones. They are very springy and absorb impacts well, for these to work effectively the open end must be facing outward from the drone. This way if you come down at a angle it will allow them to flex the most. Having them face outward also allows them to absorb vibrations & impacts well if the drone is moving forward or backwards for a slide landing. Will work with the 3mm bolt hole that the legs already have a spot for. Print them on their side so there will be no need for any support also you may want to use rafts as they will have a very small footprint on the print bed. I have had good results with PLA @ 100% infill, because of they way they are designed they still flex fairly well. However PETG or ABS may be a better option as they would flex better under harder hits. Ver 2 - Edges are now flat to allow better print bed adhesion (so thin already this wasn't really needed in the first place) and removed the hex nut opening on the inside to maintain mount thickness. If you print this and have the time, please upload a pic to the "I Made One" tab. I love seeing my designs get printed :) Thanks!
Once printing on the side, have your slicer program use a raft or a brim once these will have a small footprint on the printer bed.