PC-275AB-EB 2x5" Surface-Mount Ceiling Speaker BS5839 / EN54-24Surface mount ceiling speaker, 100V line, IP32 and EN54 24 rated. Product Features A B wiring Only 86 mm depth 2 separate 100 V transformers and 6 W speakers Quick mount Certified according to EN 54 24 Compliant with BS 5839 8: 2013 Product Specifications Frequency response: 180 Hz 20 kHz ( 10 dB from sensitivity) Connection: ceramic screw terminals x 2 Sensitivity (1 W, 1 m): 90 dB 2x 0. 5 W Max. SPL (value): 100dB Speaker component: 2 x 12 cm cone