The Wonder Washer uses a patented pressure system to force detergent and water into the fabric for a clean wash in just a few minutes as the operator turns a crank. It uses no electricity. The manufacturer, The Laundry Alternative Inc. in Nashua, N.H., claims it is gentle on clothes, using a tumble-wash process similar to that used by high-end washers costing hundreds or even thousands of dollars. There is no agitator or impeller to smack clothing.
The manufacturer explains that when you put warm or hot water into the drum, fit the lid in place and seal the machine,the air inside the drum will absorb the heat of the water and expand (i.e., just like a hot air balloon). When the air expands it creates pressure inside the drum. The pressure forces the detergent (which is diluted into the water) into and through the fabric (which is porous) about 100 times faster than you could by hand or machine. To rinse clothes, the operator adds rinse water and spins the drum for a couple of minutes.
The machine takes about five pounds-worth of clothes.