A works publicity picture of the Mk. 1a cast-iron DB200
This had many features to distinguish it from later versions including a 123/8-inch long base casting  and only 51/2 inches between centres. Although not clear from this picture, there are no V-grooves for the bed bars, instead holes were bored in the end of the casting and the bars retained by horizontal grub screws, one at each end.. The 35-mm-diameter handwheels were the second type to be employed and had a straight knurling around the edge (others have been found of 28-mm diameter, slightly thicker and with a diamond knurl pattern)

Rare and now highly-prized, this Emco Unimat is of the very first type, and almost certainly manufactured in 1954. Identification points include: crackle-black paint finish; short bed with the rails fitting into holes at the tailstock end; a nut holding the tailstock barrel in place; one-piece tailstock with a marked cantilever to the rear; no carriage lock and narrow drive pulleys with the largest diameter on the spindle to the inside  - though the pulley on the motor in the example above may be non-original. This example, unlike others seen - and probably becase it came from a faulty pattern - it has  flat tops to the front and rear walls of the cross slide casting and a crudely-finished radius where the top and front faces of the headstock meet.

Another very early type, this having a slightly better finish to the headstock casting but otherwise identical to the very first manufactured.

Another early example, this time with a wider radius between headstock top and front sloping face. The alignment bar between headstock and base was engineered by a previous owner

The comparative roughness of the castings on very early models can be gauged from this picture of the one-piece tailstock (the lower Allen bolt clamps the unit to the bed rails). Note the absence of a locking bolt at the back of the carriage