sk explosion-proof electric chain hoists from swf, including the basic models, feature powerful motors, compact installation and approach dimensions and an extremely long service life. our comprehensive quality assurance ......sk explosion-proof electric chain hoists from swf, including the basic models, feature powerful motors, compact installation and approach dimensions and an extremely long service life. our comprehensive quality assurance and stringent production controls guarantee the highest possible safety standards in operation. suitable for the following groups: eex cde iib t4, zones 1+2 eex cde iic t4, zones 1+2 complies with atex 94 guidelines, fem regulations and the european safety standards en 50014 en 50018 en 50019 spark-proof thanks to bronzed components ip 66 motor protection ip 65 cubicle protection