Set of 20 Heavy Duty G Clamps. Black Finish. For 50mm Bar. SWL 25KgSWL: 25Kg Dimensions: 155 x 105 x 25mm (Including Fixings) Weight: 340g. A set of 20 strong black 50mm G clamps with a safe working load of 25kg that would be suitable for most theatre and effects lighting fixtures. The clamps will fit aluminium tubes- wired lighting bars and trussing with a 48-50mm diameter. All the clamps are supplied with bolt and wing nut.. LIGHTING BAR CLAMP