The Black Knight Ion Element PSX Selby double pack contains two squash rackets full of technology customised for Daryl Selby. The rackets are head light with a head size of 475cm2 (73.6in2), and are strong and powerful yet controlled, stable and aerodynamically efficient thanks to Power Surge, Nano Crystalline and Thin-K technology. Vibrations have been reduced and the durability has been increased, with the rackets strung with PowerNick 19 strings for extra power and performance. Full-length protective covers are supplied with the rackets.