US 50 or 25mm circulat knitting needles

Print 2 of everything. I have included the stl files and the Autodesk Inventor files incase you would like to change anything. Insert tip 1 into the tube. Then thread wire or string through the whole on the tip of tip 2, tie a knot so the string can not come back out. Next, insert the tip with the string into the other side of the tube. Repeat with the other end of the string on the second tip 2 and insert in the second tube and attached the second tip 1 on the other end.