Bottlehead is an American company, started in Seattle, that sells tube amplifier kits to build at home. The range covers headphone amplifiers, power amplifiers, preamplifiers and speaker kits, and each amp or preamp kit comes with the wood base, chassis plates, wire and electrical parts. Chassis, wood bases and transformers are made to order in the United States. Kits are graded in three skill levels. Level One kits need no advanced soldering, so they suit first-time builders, who make up most of its kit builders. Detailed manuals and a user forum support each build.