Here's a tasty vintage biscuit for you... an original MXR Envelope Filter, made in USA in the late 70s. This is pure funk awesomeness in a box; the unassuming beige colour only adds to the intrigue. We scored this one off the original owner; he bought it new in 1978. It's in tidy shape inside and out, so if you want to add some proper vintage chíc to your board, this will surely slot in perfectly. 

Model: MXR Envelope Filter
Made: USA, 1977-8 (model made 76-83, original owner bought new in 1978)
Type: envelope filter
Power: 9v DC supply or battery
Switching: buffered bypass
Equivalent new street price (approx): n/a
Mods: 9v isolated power input added (originally ran only on batteries), velcro addded
Accessories: no original box/PSU/docs
Condition notes: used, few minor marks, very good condition