Posted by gmharris [71.105.35.249] on Sunday, January 05, 2014 at 18:00:59 :
In Reply to: NOS compress rings - what's the difference? posted by don in nh [96.61.72.163] on Sunday, January 05, 2014 at 14:42:43 :
Cast rings sometimes have the top compression ring coated in black phosphate. The inside is beveled to give the ring a twist characteristic.
Usually, the top ring gets the "trick" treatment to reduce scuffing. The top ring in a modern setup will often be chrome plated.