Worcester Access Valve. Model: 20 I 39 SWMS120 P BC R6. The Access system is a totally integrated actuation package that includes actuator, solenoid, and limit switches. Lexan cover gives clear view of (4) colored LED's. Coil continuity and voltage are verified by the orange and yellow led's. Open and closed are monitored by the green and red led's. Inlets/outlets: (2) 1-1/2 in. dia. S-line fittings. Overall dimensions: 12 in. L x 7 in. W x 15 in. H.