Customized version of http://www.thingiverse.com/thing:84258

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=84258

Using the following options:

peg_item = U
hook_width_percentage = 100
peg_length = 42
tolerance = 5
end_arm_percentage = 25
peg_offset = 25
backing_board = 6
hole_size = 5
add_shelf_support = Y