Crystal chamber with 1.11in OD, Part 1 - metal shell.
For 1.12in ID sabers (Saberforge ASP for ex)
Check this page for instructions: http://goth-3designs.com/instructions/diy-crystal-chambers/
There are 2 holes for 4-40 threaded rods, that matches with other chassis module (and sizes).
Steel material parts might require sanding.