Supply proof speaker preferred Shanghai quantity Giant. Shanghai amount giant the supply fire explosion-proof equipment, explosion-proof speaker, Shanghai amount giant the supply fire explosion-proof equipment, explosion-proof speakers, Shanghai amount giant supply fire explosion-proof equipment, explosion-proof speaker, BYS-2 proof speaker (referred to as the speaker) for constant pressure treble horn speakers ( fixed resistance) according to user requirements, suitable for installation in explosive gas atmospheres containing II C-class T6 temperature classification place for live broadcast and public address. This product meets the GB3836-2000 standard requirements. ? The speaker has a reasonable structure, beautiful shape, sound macro-volume, high-fidelity, reliable, and easy to install.