First introduced in 1955 as no 10a in the 1-75 series, the Scammell Scarab Mechanical Horse and Trailer was produced in one colour scheme: a crimson red tractor unit with a light grey trailer. Gold paint was hand applied to the cab trim. The total length of this toy was 2 1/4″ (56mm). One casting change took place which saw an extra brace added to the underside of the trailer, just above the axle. The front axle was fitted with a 6 x 18mm grey metal wheel whilst the rear axle and trailer had 7 x 18mm wheels. This model was discontinued in 1958 and was replaced by 10b which was also a Scammell Scarab but made to a larger scale, measuring 2 15/16″ long (74mm). This larger version was available with either a crimson or maroon tractor unit and a tan trailer. Initially the cab trim was hand painted gold as with the previous version but later versions had spray painted silver trim. Extra detail was also added in the form of mudguards over the rear wheels (10a didn’t have them). Early versions of 10b had 8.5 x 18mm grey metal wheels whilst later ones had 8 x 18mm grey plastic ones. The Scarab was deleted from the range in 1961.