Not a very special Dinky model, but still interesting to me, because there should be 6 versions.
Two colour versions were made during a period of 9 years from 1961 to 1970.
I have included pictures of my three models.
Two of them are in the rarer colour blue with red and yellow Supertoys hubs.
The versions with plastic hubs are on my wanted list.
This inconspicuous but beautifully finished agricultural model of a timeless prototype was introduced in June 1961. It was so successful that it lasted for ten years. It is therefore common and inexpensive. Practically no attention is paid to it in the literature.
The plastic hydraulic cylinder for the tipping mechanism holds the bucket body in any position. The rest of the model is traditionally crafted with great casting accuracy.
The yellow/red colour version is by far the most common. It has red or yellow wheels. Slightly harder ro find seems to be the yellow/blue version, which can also have red or yellow coloured wheels. In the mid-1960s, the diecast wheels were replaced by plastic ones. See Kas's contribution above.
Like all agricultural trailers, this one fitted nicely behind the 1950's Massey-Harris and Field-Marshall tractors and the Land-Rover. In the course of the sixties, more modern replacements took their place.
Jan -- You're so right ... sometimes the most successful models get the least respect. I don't think I even have one!
It also came in both gold and yellow Visi-Pac export boxes. Photos from QDT via the Dinky Toys Encyclopedia ...