The British Pedal Company Professional MKII Tone Bender OC81D from the Vintage Series is a detailed replica of the 1966 Professional MKII Tone Bender pedals created by Gary Hurst. Unlike the MKI.5, the MKII had a 3 transistor circuit which, based on production and supply, comprised of either 3x OC75 or 3x OC81D transistors and offered increased sustain. The OC81D loaded MKII can be heard on many Jimmy Page (Led Zeppelin) tracks such as 'Whole Lotta Love'. This was the pedal seen being used by Jimmy Page on the 'It Might Get Loud' documentary from 2008.