screws with opposing double threads —

Founded screws with opposing double threads models & stl files for printing
Threaded Drywall Anchor
Tennessee Mats
Threaded beads  kids toy
Vilius Kraujutis
Double letter
asad_khan
threaded insert M3
Vojta Bot
thread spool holder
Jordon's 3d printing and design
M8 SHCS screw handle
AnatolyWasHere
Screw box
federico.redaelli