Map Sensor Reducer Bung (18 to 12mm)
Map (Manifold Absolute Pressure) Sensor Reducer Bung used to reduce 18mm Sensor Holes to 12mm
This is required when the 12mm Map Sensor needs to fit an 18mm Hole
3 BAR MAP Manifold Pressure Sensor - Small Probe - 038 906 051 C
https://www.darksidedevelopments.co.uk/products/vw-3-bar-map-manifold-pressure-sensor-038-906-051-c.html
Bosch 4 BAR MAP Manifold Pressure Sensor - 0 281 006 059 / 0 281 006 060- Small Probe
https://www.darksidedevelopments.co.uk/products/bosch-4-bar-map-manifold-pressure-sensor-0-281-006-059-0-281-006-060-small-probe.html