The Filter is an all-stainless steel knife with a black-oxide BlackWash coating to protect the knife from scratches and wear from everyday use. It is well-equipped with SpeedSafe assisted opening for quick, one-handed opening with the thumb-stud or flipper. Like the rest of this series, the Filter is named for an automotive part and offers a machined look and smooth function. BlackWash gives the knife a unique “well worn” look, yet the finish isn?t just for looks. A sturdy frame lock safely secures the blade open during use, and then closes easily for storage or carry. The Filter includes our deep-carry pocket clip so the Filter rides comfortably low in your pocket for discreet carry.