Step-up Shaft Adapter 1/4 to 3/8 inches

Usually they are made of metal. I found it practical to try it using with ASA and it seems that in low torque values up to 50 ounce-force-inches this module is functioning good enough for my needs.

So, I printed it using ASA (in a closed chamber) with Brim and some support as shown on the enclosed GCODE file.   

The four holes are for M2.5 X 8 Socket Head or Pan screws.