Click to expand Tap to zoom K&N, Weld-On 18mm Oxygen Sensor Fitting for Oem H-D 18mm O2 Sensor by K&N Save £-0.83 £29.41 | / SKU MCS909895 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Add to cart DescriptionK&N, weld-on 18mm oxygen sensor fittingDetailsPlain steel. Used in any custom application were you need a 18mm bung for the exhaust O2 sensor. Fits 18mm oxygen sensors.OEM H-D 18mm O2 sensor