Customized version of http://www.thingiverse.com/thing:953856

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=953856

Using the following options:

shaft_diameter_b = 9.4
shaft_diameter_a = 5
coupler_extra_thickness = 1
coupler_mount_hole_diameter = 3.7
nut_length_b = 0
nut_length_a = 0
nut_diameter_b = 5
nut_diameter_a = 15
shaft_length_b = 15
shaft_length_a = 15