Constructed of BCY DynaFlight 97 material, Excalibur Crossbow’s Matrix Strings reduces creep while increasing speed. They also feature a proprietary center serving which significantly increases string life. – Does this work with my crossbow? Get your answer and see other accessory options here: COMPATIBILITY CHART Available in multiple colors Black PRODUCT CODE: 1992 Stingray Blue PRODUCT CODE: 1992SB Zombie Green PRODUCT CODE: 1992ZG Blood Red PRODUCT CODE: 1992BR