Keeley has unveiled the Rotten Apple, a fuzz that aims to capture Billy Corgan at the height of his Big Muff powers.

Promising a wide gain range, touch sensitivity and fat bass response, the Rotten Apple packs a switch to toggle between full, scoop and flat EQ settings.

Keeley reckons the resultant Muff V4-inspired tone is spot-on - the team even tested it extensively using an Eric Clapton Strat with Lace Sensors, just like Billy used to do. Good effort!

The Rotten Apple is available now from Robert Keeley Engineering for $149.