This knuckle roller is made out of Shedua, it's sanded up to 400grit and finish with a nice oil and wax. This profile was improved upon many times, resulting in what you see now. The ends are made of stainless steel to add more weight, which makes finger pops tricks easier to control. The length at 64mm is prefect for thumb rolls and just spinning in general. These are hand made so these sizes may vary. Length 64mm 19mm at its widest 8mm at its thinnest. 22g.