M20 x 1.5 Male to 1/2” NPT Female Gauge Sensor Sender Thread Adapter
Amazon.com: M20 to 1/2" Inch NPT thread adapters. ( $8.44 Each - Sold in 10 Packs ) M20X1.5 threads on external side. 1/2" Inch NPT threads on internal side. Nickel plated brass
Adapter M14 x 1.5 Internal Thread - M20 x 1.5 External Thread
Amazon.com: uxcell Pipe Fitting Reducer Adapter M20X1.5 Male to 1/2 G Female, Stainless Steel for Water Oil Air Pressure Gauge : Industrial & Scientific