Plated mild steel stem with open boss head fitted with thumb-screw to accept rods from 0.8cm to 1.5cm dia. Extension distance from boss head to ring is approx. 10.5cm outside diameter of ring 6cm. Clamp from Boss head centre line measures 20cm to edge of closed ring.Outside diameter of ring 6cm - Plated mild steelRing and rod are integrated with boss head clampBoss head clamps rods up to 1.5cm in diameter with metal thumb screwPlated mild steel with 0.8cm diameter rodClamp from Boss head centre line measures 20cm to edge of closed ring.