Porthole / deck hatch

A porthole/deck hatch for kayaks, boats and other similar uses. Has an opening of around 155mm diameter. The thread may be a bit stiff at first, but should free up with some use.

Update 23/12/17: Increased tolerance a bit to allow for movement/warping of the outer frame when put into a deck. Also added the countersunk holes for into the base frame (oops :D). Added an indent into the handle to make it easier to undo.