
About Eldridge Products Inc.

Eldridge Products Inc. was founded in June 1988 in Marina, California, by President and CEO Mark Eldridge. Today, with over 30 years of experience in the industry, EPI is the world’s premier manufacturer of thermal mass flow meters, switches, and metering software. With an ever-growing team of the industry’s best engineers, designers, and support specialists, EPI offers clients the reliable and accurate products they’d expect from a global leader coupled with the personal attention and dedicated service they’d expect from a world class business.
At EPI, we understand the challenges our customers face every day when measuring thermal mass flows of all types. We also understand the opportunities that accurate measurement represents to both the bottom line and to the environment. With those challenges and opportunities always at the top of our minds, we’ve spent decades developing a full line of thermal mass flow metering products that are unparalleled in their accuracy, their ease of use, and their reliability. EPI thermal mass flow meters take the headache and complexity out of repeatable, accurate flow measurement and eliminate the need to worry about expensive system downtime.
Equally as important to us as the quality of our products is the quality of our people and the relationships we build with our customers – customers who know that, with EPI, they aren’t just buying hardware or software; they’re gaining a true partner. At the core of everything we do is the understanding that our customers’ success and our own are inextricably linked, and it’s that knowledge that drives our unwavering commitment to offering the best thermal mass flow meters and the best service the industry has to offer.
The people who keep EPI up and running.

General Manager

National Sales Manager

Service Associate / Inside Sales

Operations specialist

Lead Technician

Technician

Calibration Technician

Calibration Technician

Calibration Technician

Purchase Manager

Finance Manager

Lead Designer

Senior / Lead Fullstack Engineer
A brief overview of EPI.
Introduced the Epi-Val™ with LiveZero™ In-Situ or Field Validation Field-Val™ firmware with EPICom interface for Master-Touch™ & ValuMass™ Flow Meters; BACnet communication protocol interface soon.
Moved to new 15,000 square foot facility with greatly expanded calibration laboratory.
Installed & made operable new high flow closed-loop flow calibration system.
Engineered, purchased, & built new high flow closed-loop flow calibration system.
Received Hazardous Location IECEx certification for Master-Touch™ MP Series Flow Meters.
Introduced Profibus DP communication protocol interface for Master- Touch™ Flow Meters.
Introduced our Master-Touch™ Flow Meters with Digital Sensor Interface (DSI) sensor drive with wide temperature compensation curve fit.
Established the ValuMass™ Series 500 & 400 line of low cost Flow Meters with Digital Sensor Interface (DSI); RFI/EMI certification update of Master-Touch™ & ValuMass™ Flow Meters.
Introduced HART communication protocol interface; E-Logger™ Flow Meter internal data logging into an E-Log™ file, accessible through EPI’s proprietary EPICom™ Flow Meter communication software; Introduced RS485 Modbus RTU communication protocol interface Flow Meters now include 0-5VDC, 4-20mA, RS232, Hi & Low Relays.
Received ATEX (KEMA) certification for Master-Touch™ MP Series Flow Meters; Introduced RS485 Modbus RTU communication protocol interface, LightWire™ Infrared Flow Meter communication.
Patented the Thermal Mass Flow Meter wide temperature correction method; Received CSA/CUS certifications for Master-Touch™ MP (Hazardous Location) & MPNH (Ordinary Location), Series Flow Meters.
Patented the thermal Flow Averaging Tubes (FAT™); Introduced first all microcontroller operated Flow Sensor design; Introduced self cleaning Sensor Air Purge through Master-Touch™ Insertion Flow Meter Probes.
Field tests first hybrid analog/digital microcontroller operated Flow Sensor; Introduced self cleaning Sensor Air Purge System on Multi-Point Stack Probes.
Invented 1st hybrid analog/digital microcontroller operated Flow Sensor.
Introduced the Non-Hazardous location Master-Touch™ Series 8000MPNH & 9000MPNH Flow Meter product lines.
Introduced high pressure, screw-drive probe retractor assembly; Introduced Bi-Directional Flow Meter.
Received China Pattern Approval (CPA) for Master-Touch™ Flow Meters; Introduced EPICommunicator™ or EPICom™ communication software for Master- Touch™ Flow Meters; Introduced Master-Touch™ UHP High Purity Flow Meter.
Received Hazardous Location CENELEC (LCIE) Ex certification for the Series 8000, 7000, 6000; EPI flow laboratory installed two gas provers.
Introduced the Master-Touch™ Series of fully microprocessor-based flowmeters; receives Hazardous Location CSA certification for the Series 8000, 7000, 6000; Standard outputs include 0-5VDC, 4-20mA, RS232, Hi & Low Relays; Moved to 9000 square foot manufacturing facility; Introduced Master-Touch™ Series 8000MP & 9000MP product line; RFI/EMI certification of Master-Touch™
Developed 900°F (482 ᵒC) high temperature stack insertion Flow Meter; RFI/EMI certification of Series 8000, 7000, 6000 Flow Meters.
Established Asia and Pacific Rim Distributors.
Developed 400 ᵒF (204 ᵒC) low flow axial sensor Flow Meter; Introduced the Non-Hazardous location Series 8000NH Flow Meter, 7000NH Flow Switch , 6000NH Level Switch product lines.
Established Western European Distributors; Developed high velocity Particulate Shield PS1 Flow Meter; Introduced Ordinary Location (NH) Flow Meter product line; EPI lab installed 1000°F Air Test Stand.
Developed Iso-kinetic stack velocity & sampling probe systems; Developed dual sting metal clad sensors; Developed control valve & controller; Received FM certification for Series 8000, 7000, 6000 Flow Meters.

Introduces the Series 9000 Multipoint averaging stack probes; Established an in-house flow calibration lab.

Introduced the Series 7000 Thermal Mass Flow Switch and Series 6000 Thermal Level Switch.
Eldridge Products, Inc. founded by Mark Eldridge and became a thermal mass flow meter manufacturer, introducing the hazardous area class of Series 8000 Inline and Insertion Thermal Mass Flow Meters; introduces low pressure ball valve retractor assemblies.