Sigma DG 150-500mm 1.5-6.3 APO HSM Handle/Collar

Simple handle/collar/tri-pod mount for this specific lens but if you have something with the same diameter and screw position, it might work.

This 3d print also requires external parts such as a 3.50mm screw and a 7.80mm nut to tighten the collar around the lens. If you have neither, you could also just zip-tie through the holes but make sure its secure and tight. 

Attaching the collar is a bit funny as you have 4 screws or only 2 screws like me , you have to use only 2 screws in a diagonal pattern as shown:

If you did it correctly you should be able to slide the screws through the slots on the handle and twist it to whatever position you want. 
                   
There is also some holes on both the tripod attachment and the handle itself if you want to put some 6x3mm magnets in. 

Print the tripod attachment in 0.08 so the threads actually work. 
For the extra handle extension, just glue the surfaces and slide it in. 


Let me know if I should change anything.