Modern manufacturing techniques and materials have allowed general improvements to be made over the original Panasonic / ALPS supplied fader, these include 10% overall tolerance, operating cycles increased to 15K and a more consistent carbon track application which means that these faders will not only be closer to the stated 22K resistance value but also closer to the stated resistance taper leading to more consistent calibration. In addition to these general improvements our version also has (like the original Panasonic supplied part) the two slick dummy tracks for the 0% lock switch contacts of the slide to run on rather than just running on the bare board. **Subject to the normal circuit tolerances. These are aftermarket / replacement / compatible faders that have not been supplied by or endorsed by Panasonic, they have been manufactured to a very high standard , close tolerance and ROHS compliance by an ISO certified factory therefore quality and a long life span is assured thus we are more than happy to offer a no quibble money back guarantee in the knowledge that this guarantee will not be needed. Compatible with SL-1200 / 1210 MK2 & MK3 Models.