The Blazer® Jig's unique clamp system provides more adhesion force than standard fletching jigs. It is available in two configurations. The Blazer® Helix Jig includes a black clamp to fletch a 3° Right Helical on vanes up to 2.5" (63.5mm) long and is designed for standard size carbon shafts with an OD range of .293 - .306" (7.4 - 7.8mm). It's capable of 3 or 4 fletch (4 at 90° or at 60° x 120°). The Blazer® Straight Jig includes a gray clamp that does a straight fletch on vanes up to 2.125" (54mm) long. It is designed for smaller arrows with an OD of .25" (6.3mm) or less, and is capable of 3 or 4 fletch (4 at 90° or at 60° x 120°). The nock receiver on the Blazer® Jig accommodates standard nocks. Nock receiver for crossbow bolts available for purchase separately. U.S. Patent 8,286,953 B2