1 diameter can be divided into 4 levels of adjustment carving diameter can be as small as 4mm 2 All metal structure safe and stable 3 One piece rubber roller hardness up to 60A stronger friction more stable carving process 4 Carving long cylinder small diameter cylinder conical rule objects such as tall cup 5 Linear speed is applicable to 95 of the engraving machines on the market including TEVOUP XTOOL ATOMSTACK NEJE Ortur SCULPFUN Twotrees etc 6 No installation no adjustment connect after unpacking and ready to use 7 Applicable models Frame engraving machine portable engraving machine Package Included 1 x Laser Rotary Roller