This is a Pommel Style 4 from The Custom Saber Shop, a ‘door knob’ style pommel. It’s part of the Modular Hilt System V1 (MHS V1), which works with a variety of components from The Custom Saber Shop and is compatible many Ultrasabers hilts and Sabertrio hilts as well.
Watch The Custom Saber Shop Pommel Style 4 review lightsaber TCSS on YouTube
The bottom of the two-piece pommel has a series of sound holes, narrows and then flares out again. The reason the pommel unscrews is because you can add a cube ring between the top and bottom piece of the pommel. Many people like adding a cube ring, either in the standard metallic-silver color or anodized black. Pommel Style 4 with an added cube ring looks like the Obi-Wan Kenobi lightsaber hilt pommel from Star Wars Episode I and Episode II. The pommel also looks cool, and ‘lightsabery’ without the addition of the cube ring.
The aluminum pommel adds 1.844 inches (without cube ring) or 1.954 inches (with cube ring) to the length of the lightsaber hilt.
Pommel Style 4 from The Custom Saber Shop