Click to expand Tap to zoom Viessmann Flue 100/125mm Flat roof collar flashing by VIESSMANN SKU 7426187 Flat roof collar. Metal universal flat roof collar/flashing for vertical flue terminals sized 100 mm and 125 mm. Downloads Installation Instructions Supports - Vitodens 050-W, Vitodens 100-W, Vitodens 100-W System, Vitodens 111-W, Vitodens 200-W, Vitodens 222-F, Vitodens 200-W Light Commercal Accessories