BDL - 220 v series explosion-proof electric bell Scope of applicationZone 1, zone 2 dangerous places; ... , surface spray, beautiful appearance;The 2 cylindrical flameproof surface, good explosion-proof performance, safe and reliable;3 steel tube or cable wiring ... off power before maintenance.In-build System and the rubber circle are made of oil-proof 3001, youshould contact our factory if ...