Connector, straight, 3/4 inch x 7/16 inch, with spring lock, REXNORD, spring lock, safety for roller chain, drive, drive technology, simplex, chain, drive chain. : Amazon.co.uk: DIY & Tools
Power Drive 12B-1 BS Simplex Roller Chain 3/4 Inch Pitch 5 Mtr Box Simplex Roller Chain British Standard - Bearing King