Your Face 70’s in equipped with External Bias knob in Navy Blue from the Wren and Cuff Custom Shop. Has minor powder coat imperfections and slightly enlarged in/out jack holes. Functions as intended. First photo shows an example of the pedal for sale without the external bias knob, the second photo shows where the external bias knob will be, and the rest are stock photos.

About the mod: 

Bias mod: This mod adds a bias knob that allows you to adjust how the fuzz sounds. It's a hard one to describe in text, but it will let you go from a sputtery, "wrong" weird sound, to a buttery smooth proper Fuzz Face® style sound (and everything in between). 

—See regular description below—

With the edge of a tight silicon fuzz, and some custom filtering to warm it all up, The Your Face 70's is all that's loved about the 70's Fuzz Faces, with some added tweaks to smooth things over.

We take two hand-matched BC108 silicon transistors selected for specific gains, super-quiet metal film resistors, and add smoothing capacitors to tame spiky highs and eliminate squealing at higher volumes, and that's only the start.

Don't like the low output on a traditional FF? Fixed it. All the volume you could ever want or need.

Don't like the way that a traditional FF fuzz knob is only useful at the last end of the knob? We've added a reverse-log potentiometer that widens that range and let's you dial things in just right.

Mullard “tropical fish” out-cap with increased value to allow more lows to come through. Also, Mullard tropical fish caps just look damn cool.

Custom “You” knob functions as a low-cut to reduce some of the low-end squash, letting you dial things in just right for "you". This is a simple but fantastic mod that gives an incredible amount of versatility. I've seen this mod alone turn FF haters into instant fans.

Truly an ultra-smooth high-gain silicon 70’s style fuzzer with all the right tweaks.