3/4 inches Inlet, 3 Stage. (the filters are 10 by 2 1/2 inches) and Resin, is 10 by 3 inches. It is ready to be install. Filters are in housing ready tight, comes with 2 nipples with O rings on both sides for IN and OUT connection for 3/4 inches pipes. And wrench to change the filter yourself and Shut Off valve 3/4 inches for making easier for service. You just need the 2 hoses connection, depend on your house pipes sizes. If your house has 3/4 inches pipe, it is very easy, you just need 2 hoses 3/4 inches and long enough to reach the unit and your pipes. Make sure the” IN” side connector of the Unit to be connected to the Main water supply and the” OUT” to be connected to the house pipe. Also the nipples connector do not need teflon tape because has O rings on both sides. This unit has 3 durable CLEAR housing to be able to see the filters and when to change the filter instead of planning every six months or guessing. Stage 1 sediment fine filter 5 micron, meets F. Test standard, removing everything bigger than 5 microns, and stage 2 Carbon block filter removing the chloramines (chlorine and ammonia) left over from the city water treatment center. And stage 3 Resin filter, high purity mixed bed Deionizer filter, removing minerals. This 3 stage system taking out the sediments and chloramines and minerals TDS (total dissolved solids) from your local Tap water, making great softener water for smooth and nice smell and soft skin showers and clean dishwasher , clean nice smell laundry and soft , great for long lasting Water Heather and for entire piping plumbing in your house. Great for environment, easy and cheap to maintenance yourself. If you are within Orange County, Ca. I provide affordable install and as need it services. Thank you very much. Great for single home family up to 4 persons. Mobile Homes and Travel Motor Home or Trailers. Also depends on your water TDS and how much water you use. Around 300 – 400 TDS is Bad, more than 500+ TDS is very bad water. And under 300 is good and around 100 Great. 1 grain/gallon = 17.1 TDS. My system at full water flow will filter all sediments and take out all chloramines and bring the TDS lower. Making the water more softener. Do not forget that the important is not only to make your water more softener, But it will remove all the sediments (bad stuff from the water) and the most important is that taking out all the chloramines, which to me is the worst thing in the water. I do this for living everyday for more then 20 years. The item “WHOLE HOUSE HARD WATER SOFTENER 3 STAGE CLEAR SYSTEM, 3/4 in. SALT FREE THE BEST” is in sale since Friday, August 6, 2021. This item is in the category “Home & Garden\Home Improvement\Plumbing & Fixtures\Pumps & Water Filtration Systems\Water Filtration Systems”. The seller is “nicnicro” and is located in Laguna Hills, California. This item can be shipped to United States.