Quarter turn lever washing machine valve / tap with inbuilt non return check valve.
15mm compression pipe connection on one end, 3/4 inch male BSP thread on the other (the usual thread size for washing machine hoses).
Used to isolate the water supply to a washing machine or dishwasher.
Why the check valve ??
Depending on your plumbing arrangements, water that has been sitting in the hose feeding your machine can sometimes find its way back into the water feeding your sink tap giving the water a bad taste or smell. The one-way check valve inside this item stops that from happening.
Supplied with red and blue handles.
See BSPT link at the bottom of this page for info on plumbing thread sizes.