macgng wrote:OOOH very nice, haven't seen that company's name on one before...
Search for "M.O.W. Padlock" == Minitry Of Works padlock.
I have several of these from a variety of places... There is a write up by GW about how to make a key.
Ministry of Works was only one user, most were used for gas and electricity pre-payment meters by Boards or Companies, and are usually marked as such. Keys are rare, only held by the meter-readers.
Many were removed at decimalisation, as new meters were fitted and Britain moved away from pre-payment.
The patent can be seen on the Internet. Although many were scrapped for the brass, they do circulate through the collectable markets /eBay, junk shops, but without keys so not much use. Now uncommon rather than rare.
Wormald also made several other models with distinctive keys to obviate trial of keys. A common generic marking was simply 'Property of the Gas Board', (or Electricity).