They are designed to perform at the identical or higher level than all major usa manufacturer's roller chain of the same type , Chain pitch 5/8 inch What is chain drive? Classification of chain drive Steel Roller Chain 50-1RV DID Standard Simplex Roller Chain ANSI Rivet Type Connecting Link 5/8" Pitch | Chain & Drives With Connecting Links ANSI Chain No.: #50H. Model #50 #50 #50H #50SS. Single Strand. Amount 10 feet 50 feet 10 feet 10 feet. Length: 10 feet They are designed to perform at the identical or higher level than all major USA Manufacturer's roller chain of the same Type. Brand new #50H Roller Chain 10 FT 1 Free Connecting Link- Same Day Priority Shipping Our high quality heavy duty roller chains fully meets all ANSI standards. These exceptionally durable and economically priced heavy duty roller chains have higher than average tensile strength The D&D roller chain exceeds ISO published ratings levels.