Customized version of http://www.thingiverse.com/thing:1182350

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=1182350

Using the following options:

print_height = 15
outer_diameter = 43
close_top = no
twist = 120
sides = 6
inner_diameter = 36
print_resolution = 0.3
circular_hole = yes
top_width = 1