Sram 10 spd pc1091r hollow pin chain with powerlock a chain is only as strong as its weakest link sram took this to heart when they designed their innovative new 10 speed powerchain featuring the powerlock connecting link the hollowpin construction provides smooth precise shifting and weight savings without sacrificing strength plus its the only 59mm chain with a secure tool less attachment device that youll find in cycling today hollowpin construction allows for uncompromised perfor