... 1/2")DN20(3/4" fire sprinkler different type: pendant type, upright type, ordinary type, sidewall horizontal type. Concealed typespecification:(1) ... 5) flux coefficient: 80,115(6) large coverage glass bulb sprinkler(7) 20mm diameter model: T-ZSTX20(pendent): installed downward, ... -68degree to be installed in sidewall way. ZSTDY-68degree also known as concealing type sprinkler with a round cover outside ...