I understand what you mean....i guess they make them (why not) i have never seen them though.....i would assume that most people blow out from a connection before...except when using antisiphon////i think if you blow out on the down stream pipe from the valve...and shut off the compressor...the water, or enough to prevent freezing will drain down the pipe. and then you would continue winterizing
Thanks
Ray
Rays Above and Beyond Automatic Lawn Sprinklers