Price: £8.33 GBP +VAT (£10.00)
All early water cooled T25 / T3 / Vanagon models used this coolant level sensor type (251 919 372). Push on which harness connector inside a black rubber boot. Some continued to use it up to about 1990 (probably those which hadn’t had any the the engine electrics re-engineered for a few years). Others stopped using this sensor in around 1987, and used the later type with a clip on junior timer connector which has a stainless steel clip which you squeeze to disconnect.
Either use for it’s intended purpose in a water cooled model, or just to fill the hole in the header tank if converting an air cooled model.