A backflow prevention assembly is configurable with varying lay-lengths and orientations. The assembly includes coupling assemblies and valve bodies that adjust in length and/or rotation to allow for the varying lay-lengths and orientations of the backflow prevention valves and assemblies with and without certification. A coupling assembly is connected to a backflow prevention valve and includes an outer sleeve and an inner sleeve that is slidingly received within the outer sleeve. The lay-length is adjusted by slidably moving the inner and outer sleeves with respect to one another.