This is a Tridonic 1/2x26-42 TC Pro. This ballast can run 1 or 2 x 26w double or triple turn compact fluorecent lamps, 1 x 32 or 42w triple turn compact fluorescent lamps, 2 x 18w long single turn or f shaped compact fluorescent lamp, 1 or 2 x 22w T5 circular lamp, 1 or 2 x 24w f shaped compact fluorescent lam or 1 x 40w T5 ciruclar fluorescent lamp. This ballast replaces the old 1x26/32/42 TCT Pro and 2x26/32/42 TCT Pro. Tridonic article number 22176408
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