Varuney Mfg. Industries offers Suction Coupling for Fire Protection. Varuney Mfg. Industries is an ISO 9001:2000 accredited company. Varuney Mfg. Industries supplies fire protection, fire fighting, resisting equipments, by moving of water in a controlled manner. Suction Coupling for Fire Protection is provided with shank of sizes ranging from 3" to 5½". The thread sizes of Suction Coupling for Fire Protection is as per BS:336, or ASA Standard size is 3", 4", 5", 5½". The size ranging of this coupling is 2½", 3", 3¼", 5", 5½" [BSS Standard American Standard].