Includes: This kit includes plastic washers, an O-ring, a guide cone, an E-clip, and a locking knob. CX900DA Knob Kit Replacement: The CX900DA knob kit is a replacement compatible with Star-Clear Plus Cartridge Filters models C751, C900, and C1200. CX900G Locking Knob Replacement: The CX900G locking knob replacement kit is compatible with for Star Clear Plus Cartridge Filter models C900, C9002, C1200, C12002, C12002S, and C751. Suitability Confirmation: Before purchasing, please ensure that your model is suitable for this replacement knob kit. High-Quality Materials: Made from durable materials, this kit is designed to ensure a secure and reliable connection for your pool filter.<br><br>Product Name:CX900G Locking Knob and CX900DA Pool Filter Knob Kit Fitment:for Star-Clear Plus Cartridge Filters (C751, C900, C1200, C9002, C12002, C12002S) Number of Pieces:Plastic Washers x 2, O-ring x 1, Guide Cone x 1, E-clip x 1, Locking Knob x 1 Colour:Black Material:Plastic<br><br>Package Contents: 1 * washers kit<br><br>Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.