Yet Another Low Friction Linear Bearing

Yeah, Yeah. I know this has already been done.
Here is yet another linear bearing that I designed for my Anet A8. This version is my attempt at a lower friction design. The contact surface area is about a third less than what you find in most other commercial versions. They fit tightly against both retaining rings so as not to slide around in the housing. They also fit snugly around the 8MM Rod

Measurements: All are for 8MM Rod
Standard Bearing: 15MM OD, 24MM L
Standard Z Bearing: 15MM OD