All BeadPens are entirely constructed of metal, and have an extremely fine anodized finish. The BeadPen is designed to be perfectly balanced after placement of lampwork beads. The overall length of each BeadPen is 15cm. The usuable length of the rod for placement of beads is 64mm. There are extra threads on the rod which allow up to 3mm of additional adjustment. The mandrel (rod) is 3/32" (2.4mm) which fits most lampwork beads.