Reactor Pedals is a small, hand-built guitar effects pedal builder based in Nottingham, England. The operation grew out of a personal attempt to clone a Harmonic Percolator using vintage components, and that circuit remains central to the brand's catalog. Each pedal is assembled by hand with through-hole construction, true-bypass switching, and hand-finished enclosures, and the builder emphasizes that component variation gives each unit its own sonic character.

The lineup centers on Harmonic Percolator–style fuzz/overdrive units. The AZ-5 uses vintage 2N404 germanium transistors made by Texas Instruments in the 1970s, paired with additional diode clipping options for tonal flexibility. The AZ-5r is a Russian-loaded variant built around MP16b transistors and D9K germanium diodes (NOS, sourced from Russia), tuned to span a smooth low-gain drive through to a more aggressive, crunching overdrive. Pedals are sold direct via the brand's Reverb storefront and ship with a two-year warranty.

Reactor Pedals has 2 products cataloged on Equipboard.