A TDK-160 research assistant represented a reconfigurable droid design. Its movement system was adaptable, allowing for the substitution of two thin legs, a dual-tracked system for traversing difficult landscapes, or even alternative configurations. This droid was noted to possess "sloping shoulders." A specific unit of this type, which provided support to Galen and Lyra Erso on the planet Vallt, acquired the moniker "Assis."