ES classified fire dampers with reduced smoke leakage characteristics (BS EN 1366-2). External blade position indicator. AB (37-38, 44-45 & 53-56), BT (Northern Ireland), CA (18-27), HS (Outer Hebrides), IM (Isle of Man), IV (7, 9-12,14-28, 30-32, 36, 40-56), KA (27-28), KW (Orkney Islands), LA (15-23), PA (20-38, 41-49, 61-78, 80-88), PH (17-26, 30-44, 49-50), TR (21-25) & ZE (Shetland Islands).
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