1/2" with a step up connector to 3/4" to fit the windtech shock mount...I made those for my 1m AB spaced bar...they come in handy when I run two stands and microphones spaced out on Stage Lip too...
I really like the DIN and DINa stereo bars...3/4" and 1/2" with 1/2 Street connectors to make the 45degree angle.
Although it may not be very visible...On all these there is a Saw Kerf cut to make a slot that relieves tension and allows you to snake the mic cable out...