After enquiring through (one of) your dealers and calling EI directly it was clear that you provided good customer service and would likely not drop the ball on tech support, and so far I have been right.
A-1 Carb or OAT Instrument
Don’t Need Your Glasses To Read
- Large digital backlit display.
Interpret Your Readings Faster
- The digital display allows for quick trend analysis.
Budget Friendly
- Same precision found in the most advanced analyzers on the market, but the A-1 Carb or OAT Instrument won’t break the bank.
Accurate, Dependable & Easy To Use
- LCD sunlight viewable and backlit for night operation.
- Electronics International consistently has been a leader in digital engine instrumentation since 1979.
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Product Overview
A-1 OAT Overview

OAT or Carb Temp
Electronics International’s A-1 instrument provides pilots with the precision and stability needed in order to accurately monitor Outside Air Temperature or Carburetor Temperature while in-flight.
Ice Zone Warning
Not only will Electronics International’s A-1 display Outside Air Temp with a stable, one-degree (Fahrenheit) resolution, it also comes complete with an “Ice Zone” light that alerts the pilot when the Outside Air Temperature could possibly contribute to ice forming in the aircraft carburetor.
Reliable Probes
A-1 OAT Kit Includes:
- One (1) P-110F Fast Response EGT Probe
- One (1) P-100 CHT Probe
- One (1) P-128 OAT/Carb Probe
A Monitor is only as good as its probes. That’s why Electronics International (EI) has taken the development of its probes, connectors, and accessories very seriously. EI has been designing and manufacturing probes for over 30 years. All of our probes have been designed in-house by our engineering team. Our team has studied, tested, and designed temperature probes since the 1970′s. They have written research documents such as The Pilots Manual – Leaning and Diagnosing Engine Problems and Accurate CHT Measurements. Just as a Monitor is only as good as its probes, a probe is only as good as its connector. That’s why EI’s engineering team developed EI’s proprietary OLC-1 connector. The OLC-1 connector greatly increases reliability and reduces installation errors as compared to traditional type connectors. Whether you’re looking for a reliable and accurate CHT, EGT, TIT, or various other probe types, EI has what you need. With more than a half million probes sold and tested you can count on EI’s reliability.



Prices
Retail Prices
Package includes:
- A-1 Carb or OAT Instrument
- P-128 OAT Probe
- XP-6′ Precision Thermocouple Cable
- Wire Harness
- Operating & Installation Instructions
Description
Package
Retail Price
A-1 Carb or OAT Instrument
-
$428

Specifications
Specifications
Dimensions
2.5″ x 2.5″ x 3.65″ Deep, 2 1/4″ Flush Mount
Weight
7 oz. (Unit), 1.6 oz for a probe & 2 oz for a 6′ Cable
Power Requirements
7.5 to 30 Volts, 1/10 Amp
Ice Zone Warning
Light is lit when displayed temperature is between 10°F and 39°F.
Display
Viewable in direct sunlight, with dimmable 12 and 24-volt backlight control lines.
Intensity Control
Separate intensity control lines allow you to independently control Ice Warning Zone and Backlight intensity.
Probes
Type K Thermocouple, Ungrounded

Videos
Product Videos
Documents
Documents & Manuals
Testimonials
Customer Testimonials
Very impressed with the clarity and readability of the CGR-30P gauge.
- Customer
Richard K. from New York
- Aircraft
Piper PA-28-181 Archer III
- EI Instrument
Compact, precise, awesome!
- Customer
Harvey C. from Maine
- Aircraft
Cessna A185F Skywagon and AgCarryall
- EI Instrument
Customer Service is far superior… with an excellent record of resolving … technical issues.
- Customer
C.J. R. from North Carolina
- Aircraft
Mooney M20C Ranger
- EI Instrument
I have been flying with EI instruments for over 20 years. I purchased the CGR-30P to update my engine instruments into one modern package.
Great customer service!
The installation was straightforward and quite easy. Reliability and accuracy far exceed the original [aircraft’s] oil pressure/temperature systems. Also, the price was about a third of the cost to replace the gauge cluster.
- Customer
Casey R. from Oklahoma
- Aircraft
Cessna 172M
- EI Instrument
Awesome product. Fast easy installation.
- Customer
Rodney E. from Georgia
- Aircraft
Cessna 172M Skyhawk
- EI Instrument
I have worked with your products before and I like them.
- Customer
David K. from New Mexico
- Aircraft
Cessna T20N Turbo Centurion II
- EI Instrument
Very easy to install. Harness is clearly marked. Instrument worked first time. The instrument is intuitive and easy to use.
- Customer
William F. from Maryland
- Aircraft
Mooney M20C Ranger
- EI Instrument
The [unit] is easy to read and quick to respond. I have multiple EI units and have had good experiences with all.
- Customer
Thomas C. from Maine
- Aircraft
Maule M-5-235C Luna Rocket
- EI Instrument
Really impressed thus far . . . . a rock solid replacement for old mechanical gauges.
- Customer
Eric H. from Mississippi
- Aircraft
Beechcraft C23 Sundowner
- EI Instrument