This 303 stainless steel barrel adjuster is threaded M5 x 0.8 to fit all threaded cable stops. It is 24 mm long and has a 9 mm hexagon, 6 mm housing hole, and a 3/32" through hole to clear all cables. The spring is not included but is available through McMasterCarr, P/N 1986K63 .
Item sold individually.
Photo courtesy of CERNITZbike