This pulley is used on the Lister CS water pump kits but for the purpose of the charging alternator on the higher speed 1000rpm engines we have made it available separately. This pulley is bored for the 2" diameter CS crankshaft and the outside rim is machined to suit an A profile V belt. Please don’t forget we have access to a huge range of power transmission components, if you cant find what you are looking for please contact us with your requirements. We will be very pleased to help.