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How to understand GE Panametrics M-Series Probe part number  A Model M Aluminum oxide moisture probe B Mount 1 Flange mount process connection with Viton O-ring, 300 series ss. 2 3/4 inch - 16 straight thread process connection with Viton O-ring, 300 series ss. 2N 3/4 inch - 16 Straight thread process connection mount meets NACE requirements. 7 auto insertion mechanism type 1 inch NPTM process connection 2800psig max press Note- 1" fully opening ball valve required for isolation purposes 9 1-inch VCR gland mount; 316 SS Note- Requires a 2891 sample cell C Hygrometer Designation 1 For use with MIOOO Hygrometer 2 For use with M2000 Hygrometer 3 For use with M3000 Hygrometer 4 For use with M4000 Hygrometer L Calibration range of -8...