Duckhams is perhaps the most well-known British oil brand from the 60's and 70's, and still features its famous green colour. They were instrumental in the development of multigrade oils in the UK, and the famous yellow and blue logo adorned many competition cars of the period.

duckhams classic sae30
Duckhams Classic SAE30
Duckhams green winter-weight monograde for a wide variety of pre-1950 applications (1 gal)