I designed this adapter after having struggled to find the right adapter to inflate an air mattress. After hours of printing and tweaking, I'm very glad to share my first design with you!

!!Notes!! : This print only takes 1.5 hours and is easily printable standing up (with the Schrader valve touching the printer bed, as shown in the fourth picture). I would recommend printing this adapter with a layer height of 0,15mm, a brim is necessary ( a raft is recommended when printing with a non-stick surface or unleveled printing bed) and zig-zag support between the largest diameter and the bed (as shown in the fifth picture).