highfrequency welding machine 1. professional for welding tent, canvas, inflatable PVC, fabric, tarpaulin products, blow air toys, shoes, tent,raincoat,bath shade,air bed, breath ship, swimming ring, decorate board for cars, all PVC PET leather product. 2. Features: 1) NL-5557 anti-spark vacuum tube protection device 2) With double sides slipway, accurate position and flexible action 3. Parameter: Model: WS-4000S / WS-5000S / WS-8000S / WS-10000S / WS-15000SD Power output: 4,000W, 5,000W, 8,000W, 10,000W,15,000W Voltage: 50 / 60HZ, AC380V, 3P Power input: 7kVA, 9kVA, 15kVA, 18kVA, 25kVA Rectifier: silicon rectifier Oscillation tube: 7T84RB / 7T85RB / E3185 / 7T69RB / E3069 8T85RB / E3130 Anti-spark thyratron tube: NL5557 Pressure way air pressure gap of electrodes: 250mm / 150mm / 150mm upper board: 200 x 350, 200 x 350, 400 x 600, 600 x 800, 700 x 900 lower board: 400 x 600, 400 x 600 600 x 800, 800 x 1,000, 800 x 1,000mm Overall Dimension 660 x 1,350 x 1,730, 660 x 1,350 x 1,730, 1,000 x 1,800 x 2,500, 1,000 x 1,800 x 2,500, and 1,000 x 1,800 x 2,500mm N.W.: 400kg, 400kg, 500kg, 700kg,900kg