Work-class ROVs are built with a large flotation pack on top of an aluminum chassis for the necessary buoyancy. The construction of the aluminum frame varies depending on the manufacturer’s design. Operators may fit a tooling skid at the bottom of the system to accommodate sensors or tooling packages. Syntactic foam is often used for the flotation material.
Smaller than work-class ROVs, survey ROVs are often sub-classified as either Class I: Observation Only or Class II Observation with payload.