In 1973 it was OK to have a dragster steam roller, those guys at Lesney must have been smoking something heavy duty to come up with these ideas you know. This one has a nice quirky feature in that it is actually steered by the steering wheel or tiller.
The Rod Roller (21e) was released in 1973 and stayed in the range until 1978. It is always yellow but the wheels can be black, metallic red or matt red. There is usually a comet sticker on the bonnet, but not always - same as the Vauxhall Guildsman (40d). The one to look for is the one with metallic red rollers.
