Carbon Express Medallion XR Carbon Target Arrow Shaft Matched Set - All Medallion-XR series 12-pack sets are sorted and matched by weight for best-in-class consistency. Weight sorting tolerance is +/- 1.0 grains. Spine selection sorting tolerance is +/- 0.0025" Real Straightness - Every Medallion-XR is laser checked for straightness to a remarkable 1/10,000 of an inch. The Medallion-XR is checked to a straightness of +/-0.003 as a maximum measurement, not an average Precision Components - The Medallion-XR can be equipped with an assortment of precision components ranging from Soma Nocks, pin nock adaptors to a variety of adjustable points Item specifications: 600-Size, 6.7 to 6.8-GPI, 0.600-inch Spine and 0.239-inch Diameter