The Brunsviga 13RM is a late-model machine in the traditionalOdhner format, with both the counter and accumulator registers inthe moving carriage at the front. The machines were built by the Olympia factory in Spain from 1964 until the close of production in around 1970. This particular machine was housed in a heavy wooden carrying case and was used for field work by surveyors from the Department of Main Roads in the state of New South Wales.

The 13RM has die-cast alloy covers in 1960s styling, but themechanism is still built in traditional Brunsviga fashion with plentyof cast iron and brass. The machine has a check register above the setting levers, a rotor quick-clearing lever at the right-hand rear, an Odhner-style back-transfer mechanism, and tens-carry with automatic reversing on the counter register. A lever at the top left of the machine indicates the counter direction, and allows for manual setting. The counter tens-carry mechanism uses an odometer-style register with a set of cam-driven pawls to assist with ripple carries. All of the operator controls are on the right-hand side to allow one-handed operation.