https://www.latis-service.com/en/products/nuoval-line/acv-automatic-control-valve-diaphragm/1394
M3620-M2620 - T.i.S. Service
The ON-OFF FLOAT CONTROLLED VALVE AND PRESSURE SUSTAINING, control the minimum and maximum level of a tank, allowing to maintain a minimum adjustable upstream...
t iservice
https://her.nottinghamshire.gov.uk/Monument/MNT14759
M3620 - LANGFORD MEDIEVAL VILLAGE - Nottinghamshire Historic Environment Record
medieval villagehistoric environmentlangfordnottinghamshirerecord