Myron L (442-300) 442 Natural Water Standard Calibration Solution 300 PPM Pentek (155309-43) 20"x2.5" CBC-20 Carbon-Briquette 0.5 Micron Filter 5" cartridge engineered for dual-action

5" cartridge engineered for dual-action filtration

Works With Hanna Photometers

5" Softening Resin Cartridge

40°F – 100°F

The 1/4" compression port accommodates standard tubing used in most residential filtration systems

Myron L (442-300) 442 Natural Water Standard Calibration Solution 300 PPM Pentek (155309-43) 20"x2.5" CBC-20 Carbon-Briquette 0.5 Micron Filter 5" cartridge engineered for dual-actionMyron L Myron L 442 Natural Water Standard Calibration Solution 300 PPM Industry standard calibration solution for natural water TDS testing across municipal, industrial, and environmental applications Model 442 300 300 PPM Natural Water Standard 442 Salt Formula The Myron L 442 300 calibration solution has been the world's most accepted natural water standard for over 35 years, formulated specifically to match the variable salt composition found in