Conex Equal Union Push-In Fitting by PrevostThis Prevost Conex equal union joins two air lines of the same diameter with a straight, inline connection. The push-in ends grip the tube automatically, so you get a quick, secure seal without threading or clamps.Like the rest of the Conex range, it works cleanly with our other push-to-connect fittings and sits alongside the complete lineup of unions for joining and extending compressed air runs.