This is an original extension. It can be attached to custom cues and other manufacturers' cues. It can be used without modification, simply 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 (confirmed to fit on a Cognoscenti cue in my possession). MEZZ extenders can be attached. Also, by attaching an X-bumper, you can also attach a MEZZ extension. Length: Approximately 1 inch Weight: Approximately 25.7g Bolt Length: Approximately 3cm ⚠️MEZZ original butt rubber is not included. If you wish to purchase multiple items I have listed, please leave a comment, and I will discount the shipping cost. This is handmade, so please purchase it if you don't mind minor imperfections. If you have any questions, please leave a comment. I will try to respond as quickly as possible, but please understand if there is a delay due to work or other circumstances.