milos Half Conical Connector voor p serie truss M12 Thread. For Pro-30 TrussThe PRO-30 is standard made of 50mm alu-pipe with a thickness of 2mm, or to an extra charge PRO-40: 48mm alu-pipe with a thickness of 3mm. This is the most known and used construction system for discotheques, stages, theatres and for many more applications. The PRO-30 is available in following models: 2 point (Step system), 3 point (Traingle) and 4 points (Square system). The system elements are joined with help of the proved conical connection coupling.