Exd IIBT6 limit switch box ALS-500 series provides a product of high performance, safety and compactness for hazardous area. With exquisite and pleasing appearance, durable service life, the housing complies with E Ex, IECEx, ATEX, dust explosion-insulating (DIPA20 TA,T6) standards.Explosion-proof grade: Exd II BT6 DIP A21 TA, T6.