GARDENA L-Piece Male Thread, 25mm by 1/2-Inch

Works well and easy to install, but also fairly easy to break. Be careful screwing your sprinkler to the fitting. Don't use much tape.Expensive and sometimes vendors on Amazon jack up the prices when they are low on stock.Installation to the pipe can be tricky, be sure to insert until you have a click and then go another couple of centimeters.Edit: third one broke out of 15, so this is weak. Treat it like glass. Don't use thread tape and tighten each fitting super carefully.