First battery-powered flashlights appeared around 1899 with dry cells. David Misell patented the first flashlight in 1899. LED flashlights replaced incandescent bulbs in early 2000s
Electrical wiring includes cabling and devices installed in structures. Safety standards vary by location and country. IEC harmonizes standards but significant variations remain
Sirens are loud noise-making devices used for civil defense and emergency vehicles. Mechanical sirens use rotating disks to produce sound, while electronic sirens use speakers. Fire sirens often serve as both warning and emergency signals. Sirens are mounted on fire stations, government buildings, and tall structures
Magnesium stearate is a white, water-insoluble powder with formula Mg(C18H35O2)2. It contains two stearate anions and one magnesium cation. Produced by reaction of sodium stearate with magnesium salts or magnesium oxide
Guidelines developed by Commission's Working Group "Pressure". Guidelines replace Directive 97/23/EC as of July 2016. Guidelines follow format X-yy, where X indicates subject and yy is sequential number
Flame retardant case and cover meeting UL1778 standards. Self-resealing vents and hermetic sealing for leak resistance. Absorbed Glass Mat (AGM) separators for electrolyte absorption. High performance brass threaded receptacles and faston terminals. Computer optimized electrochemistry for increased power up to 1.67V