Replacement piston and end plug assembly

Compatible with:

• CSI Signature 1, 2, and 3 softeners and filters*
• Watersoft Isobar 2 & 3 softener and filters**

*Except for CSI Nitro Filters manufactured after 6/1/2015, which use 20009X231

**Except for WaterSoft Centuri Filters manufactured after 6/1/2015, which use 20009X231

Anytime you're replacing a piston, we recommend also installing a new seal & spacer kit.