Our Compression Unicheck is an 1-1/2'' full flow check valve for backflow prevention in basement sump or drain pump applications. The compression fittings on each side of the check valve allow for quick and easy connection to SCH40 PVC. The Compression Unicheck can spliced into an existing line very easily as there is no need to thread it into place. It can be used in either a vertical or horizontal position.The compression fittings also enable a pump to be easily removed when there is a need to do so. Thus eliminating the need to cut the discharge pipe. This lessens the time required on a jobsite for replacement and repairs.The full-flow design of this check valve allows the internal flapper to open to match the internal diameter of the connected line. So you never have to be concerned about the pump passing solids that the valve is unable to handle. Peace of mind right out of the box!