*PLUMBERSSTOCK EXPERT* responded:
Good question! You will know what series your K-Rain distributing valve belongs to by its product number. If the product number starts with "4", it is a 4000 valve. If it starts with "6", then, it is part of the 6000 series. Please see this Specification Sheet for reference. This K-Rain P8003050 stem/disk is used for the 6000 series. If you have a K-Rain 4000 distributing valve, the K-Rain P7005511 is the one that will work for you. If you're ready, simply add it to your cart to start placing your order. Thanks for seeking answers from PlumbersStock.com!