Zenith Archery Products Bitzenburger Upgrade Kit

Easy to install and feels like theirs less slop in the dial. 4 stars because it doesn't come with all the inserts needed. Apparently 5mm requires an "x" adapter that's not included. strange not to include the piece necessary to fletch one of the most common arrow diameters.

Zenith Bitzenburger upgrade kit

This upgrade kit is awesome. It keeps the arrow from any movement and eliminates any inconsistencies. I did add some lithium grease to the internal parts including the springs and the bearings of the dial to reduce wear to the aluminum. It has made my Bitzenburger into a more precise and precision arrow fletcher. I highly recommend this product and installation was easy due to videos on utube. Works smoothly and flawlessly.