This is a Clearinse CR2 deionized water filter for spotless boat rinsing to avoid hard water spots. It is the upgraded model with the digital flow meter so you know when to recharge the system with salt. It works extremely well and is built like a tank. I just rebuilt the unit with brand new: resin tank and resin, carbon filter and housing, shut off valve and digital flow meter. Look at my 100% feedback and buy with confidence. Thank you for looking at my listing. Local pickup only.