Big-Bang Model 60MM

Introduced in 1958, the Big-Bang model 60MM is based on the 6F one-piece casting, substituting rubber tires in place of the iron wheels.
Two types of tires were used. The earliest ones were marked "Premier U.S.A. 1100 X 20" and have a military tread. The later tires are un-marked and have a tractor style tread.

This 60MM has the Primere tires.

This example shows the tractor tires.

Here is another Primere with the saddle box.