RKI 03 Series Single Gas Detector Calibration Kits The shock absorber unit is

The shock absorber unit is encased in UV-Resistant transparent plastic for easy inspection

Self-cleaning

It cannot be used in tandem with a P100 filter

Low maintenance

The Gentex Pureflo PR02020SP PAPR HEPA filter is sold by the box of 8 each

RKI 03 Series Single Gas Detector Calibration Kits The shock absorber unit isThis item has been discontinued by RKI. The replacement, the 04 Series. Please also consider the GFG Micro IV single gas detectors. The RKI 03 series is the go to single gas detector for repeated use applications. You can replace the battery (which provides nearly 3 years of run time) and the sensors. And the best part is that the sensors are inexpensive and easily field replaceable. Not to mention they are interchangeable with RKI's GX 2009 and GX