The Pignose amp, now known as the "Legendary 7-100", is a battery-powered, 5-watt portable guitar amplifier with one 5" speaker. It was invented by Richard Edlund  and Wayne Kimbell in 1969. The Pignose weighs five pounds and includes buttons for a guitar strap; it is considered the first portable electric guitar amplifier . The 'legend' was established when the inventors gave 65 prototypes (with flexible rubber Pignose volume knobs) to some of the most famous musicians of the era, including Led Zeppelin , The Rolling Stones, The Beatles , The Eagles , and The Who . Terry Kath (of Chicago), was given one which led to a partnership with the group and its management team in 1972. The first production Pignose amps debuted at the '73 NAMM Convention in Chicago. The original Pignose 7-100 is still in production and is used primarily as a portable practice amp. It has also found a role in recording studios, having been used on records by Joe Walsh, Eric Clapton and Frank Zappa. In 1985, Pignose Industries was acquired by Howard Chatt and is now called Pignose-Gorilla.
The 7-100 has a few notable features, the first being the buttons to fit a guitar strap to it. This was to make an electric guitar playable while a person is traveling (as a way to hold the amp). The 7-100 is powered by six AA batteries or an optional AC adapter and weighs between five and six pounds (2.27-2.72 kg). Another feature is the hinged case design, allowing the user not only to store objects like the cable and strap inside the amp, but also to open the case slightly to alter the sound to their preference . If a friend is around, they can also open and close the case for an improvised wah effect. A feature for the more serious musician is the preamp output jack on the rear, allowing it to be connected to a larger amp for use as a guitar distortion effect .
In addition to the original Pignose 7-100, the company offers two other battery-powered portable models called "Hog" that use integral rechargeable batteries, as well as standard amplifiers, both solid-state and tube-based .