HQUA-TWS-12 Ultraviolet Water Purifier Filter for Whole House Water Purification, 12GPM 120V, 1 Extra UV Lamp + 1 Extra Quartz Sleeve. This Item is New – Open Box. 21″L x 3.5″W x 3.5H. 12 Gallons Per Minute. 304 Stainless steel chamber, 2 UV bulbs, 1 quartz sleeve, 1 electronic ballast, 2 plastic brackets holder, several o-rings. 12GPM 55W 21 inch long and 3.5 inch diameter. MNPT Inlet/Outlet: 3/4 Inch DN20. Idea from BIg Blue. Smaller Size, Easier to Install and integrate into the pipe system. No change in taste, odor, pH or conductivity nor the general chemistry of the water. 9000 hours Life of UV bulb. Efficiency purification: Reduce bacteria and viruses. Professional manual book are contained. Installation, maintenance, troubleshooting are easy to finish with that.