A Locost is a home-built car inspired by the Lotus Seven. The car features a space frame chassis usually welded together from mild steel 1 in × 1 in square tubing. Front suspension is usually double wishbone with coil spring struts. The rear is traditionally live axle, but has many variants including independent rear suspension or De Dion tube. Body panels are usually fibreglass nose and wings and aluminium side panels. Each car is highly individualized according to the resources, needs and desires of each respective builder.

The Lotus Seven is a sports car produced by the British manufacturer Lotus Cars between 1957 and 1972. The Seven is an open-wheel car with two seats and an open top. It was designed by Lotus founder Colin Chapman and has been considered the embodiment of the Lotus philosophy of performance through low weight and simplicity. The original model was highly successful with more than 2,500 cars sold, due to its attraction as a road legal car that could be used for clubman racing.