simple plastic tube filled with shiney stuff, bolt in van (there not very big) plug hose in one end (hose lock connector) and length of hose out the other side into tank, it's as easy as that, it's like a big britta filter, doesnt stop water pressuer either
But every 150 gallons they need flushing with salt, just as easy unplug hoses swap them around so water "in" now goes through a salt container and into the "out" of water softner and a length of hose on the "in" going down a drain / sewer, it takes about 20 mins to complete dont let them tell u it only takes 5
salt is about £5 a bag and will last about a week with a TM so a porty will last you ages, not sure how much they cost as got mine with the machine buut there not dear
James