This is a new oil filler cap Not OEM with pressure gauge for Busch R5 rotary vane vacuum pump models from 0160-to-0630 (all B, D, RA and RC models). This cleverly designed oil filler cap incorporates an easy-to-read, color-coded gauge which indicates when exhaust filter replacement is needed. This inexpensive accessory is a must have to maintain your pump's health and longevity.