Beginning in the mid-1960s many brands of travel trailer (including Airstream) used Thetford waste valves. Although Thetford valves are rarely used on new trailers, some of the parts are still available. Thetford valves have four bolt holes at 4-1/4" on center.
Attn Airstream owners: If your trailer is 1964 or older, you do not have a Thetford system. Your waste fittings are an obsolete standard.
Beginning in the mid-1960s many brands of travel trailer (including Airstream) used Thetford waste valves. Although Thetford valves are rarely used on new trailers, some of the parts are still available. Thetford valves have four bolt holes at 4-1/4" on center.
