ATV Flail Mower 120 CM Width. ATV Flail Mower (120cm) with XR2100 420cc Briggs and Stratton 4 stroke electric start engine 13.5HP. Technical Specifications Electric Start XR2100 Briggs and Stratton engine 4 Stroke OHV petrol engine Heavy duty towable frame. Call David on 07825 911829 for more information we can deliver by Pallet to anywhere in the mainland UK.