These are handmade, hand-wired clones of an old school sustain "module" originally made in the late 60's by a great NY effects company. These were a cut-down version of the famous fuzz/sustain pedal made in a small box to plug straight into your guitar. The circuit is VERY similar, using 2N5088 transistors, like the original, although I have added a volume control for more versatility still. This version is in my hand made custom built stainless steel enclosures with true bypass and LED.
These are more of an overdrive with a fairly flat mid response and good bottom end. Not huge output and with a little "crackle" around the edges of the distortion. Check my blog for more details.
My designs are inspired by the classic old units but with modern components and appointments and many options like true bypass or non-true-bypass switching, LED's, added "active" tone controls, boosts and "Boss" compatible 9-volt adapters. NONE of my pedals use batteries.