Check the listing for details. Lusithand Devices Double NFP MKII, Wal style active onboard filter preamp. Color: N/A, Condition: New. Listed at 249.00 USD. IMMEDIATE SAME DAY SHIPPING Double NFP MKII The 'Double NFP MKII' is a filter preamp like the ones seen on basses like the Alembic or Wal. Being low-pass filters, it lets all bass frequencies pass through up to 2.5Khz where it starts cutting. The cutoff point has a resonant peak that can be boosted by pulling-up on the potentiometer. The potentiometer also allows you to sweep the cutoff point(resonant peak) within a range of 100Hz to 2.5khz on the Neck and 200Hz to 2.5Khz on the Bridge. The 'Double NFP MKII' has one filter per pickup ,offering more tone shaping options, that are actively mixed through the pan/ blend potentiometer and into a Master volume potentiometer. The Master Volume has a push-pull function, labelled 'Attack', which boosts between 4 & 8Khz . The gain for the 'Attack' function can be set with the 'Attack' gain trimpot on the Blend board. Atten trim pot: if pickups are too hot, causing clipping, use these trimmers for attenuation. It ships set to 0 attenuation. Q trim pot: increase the resonance for each filter using these trimmers labelled 'Q'. Attack trim pot gain: adjust the gain level of the treble 'Attack' function.Operation: 9 to 27volts Current Draw: +- 2.9 mAh Dimensions: Filter boards x2: W: 3.3cm; H: 2.3cm; D: 1.7cm Potentiometers:: Hole size is 6.5mm, and bush height is 10m, (use with 6.4mm knobs) Blend board x1: W: 3.9cm; H: 2.5cm; D: 1.3cm WORKS WITH PASSIVE & ACTIVE PICKUPS.MSRP : $309.00 Lusithand PREMIUM CUSTOM KNOBS now available, check out my other listings.For lots of great videos of LUSITHAND high end products, go to YouTube. Latest nice video demo by Public Peace on YouTube. Youtube Videohttps://www.youtube.com/watch?v=9N46vtayBl0