4" Double female section with 12 grooves and 24 8-32 threaded holes.
Screws need to be 1/8" long in order to not interfere with the threading.
All MHS parts should have the threads wiped clean and then lightly oiled or greased. We sell some
Synthetic Grease for this. Parts that get stuck because no oil/grease was used or that are damaged by the user trying to take them apart will not be warrantied.