Anti-dust and dust tested and found to comply with the DIN EN 60529 standard. Talc suspended in diffuse dust bin, all tested components like cover with a layer of fine white sand powdered sugar. Then use the vacuum pump into a low pressure environment, so that dust can enter all the nooks and crannies, but CEE plug and socket internal remain clean and dust-free heat-resistant CEE plugs, sockets, fire-resistant and high heat-resistant performance is detected with a red-hot electric wire synthesis of a 650 degree heat of the hot wire contact the insulating material of the housing 850 degrees to contact plugs, socket contact carrier insulating material to take up to 30 seconds to open the hot wire, caused by the flames go out of sight and the back of the unit under test bottom Spirit Minsi quality test paper, however, will not fire through the detection of "safety first" anti-cold, even at very low temperatures, special synthetic material can still maintain its strength and toughness and mechanical strength to go through the percussion and drop test. frozen 16 hours in a freezer at -25 degrees, plug, socket after falling from 75 cm high, is still intact. waterproof set of CEE plugs and sockets in the water 7.5 meters deep in the water, its the simulation 0.75 bar pressure the end of the detection, the inside of the product remains dry, the anti-immersion class standards. transfer ring nozzle mounted in a standard needle-like jet of water ejected from the ring angle aligned the entire spray process lasting at least 10 minutes without a drop of water can penetrate into the mix inside the unit so that by Level the IP4 splash test