This is an original extension. It can be attached to custom cues and other manufacturers' cues. It can be used without modification, just by removing the butt rubber and attaching it. Compatible with: Cognoscenti Jacoby Richard Chudy Lambros Adam etc. It can be attached to any cue that accepts a 3/8-16 thread bolt. ⚠️If the bolt length is correct, it may be possible to attach it to other cues, but please do so at your own risk (verified for installation on my own Cognoscenti). MEZZ extenders can be attached. Also, by attaching an X-bumper, you can also attach a MEZZ extension. Length: Approximately 1.5 inches Weight: 35.5g ⚠️MEZZ genuine butt rubber is not included. If you wish to purchase multiple items I have listed, please comment, and I will discount the shipping cost. This is handmade, so please purchase if you are not concerned about minor details. If you have any questions, please comment. I will try to respond as quickly as possible, but please understand if my response is delayed due to work or other circumstances.