[I chose EI because they offer a] certified replacement vs. back-up only and they look great.
- Customer
Nic C. from South Carolina
- Aircraft
Piper PA-28 Cherokee
- EI Instrument
8am–4:30pm PST M–F
Open Now
Our TR-1 provides exceptional performance, reliability and features. If you need to replace or overhaul an old failing instrument, consider buying one of our TR-1s from a company which has been designing quality aircraft instrumentation for over 40 years. Purchasing our TR-1 is substantially less expensive than overhauling or replacing your old needle gauge. We’re able to make this offer with a money-back guarantee because we’re confident you’ll love the performance, reliability and features these instruments offer.
| Amps | AOA | Bleed Air Temp | Cabin Pressure |
| Diff Air Pressure | EGT | EPR | Fuel Flow* |
| Fuel Level | Fuel Pressure | Hyd | ITT* |
| NG/N1* | NP/N2* | O2 Pressure | OAT |
| Oil Pressure | Oil Temp | TAT | TGT |
| Torque* | TOT | Volts | And More! |
* See Product Page
We offer one package option for our TR-1 instruments: Premium. The Premium TR-1 package is targeted for customers that need to minimize AOG time.
Bluetooth Field Calibration Device [FCD-TR-1] (add $600)

Dimensions
2″ standard round, 4.23″ long
Weight
0.3 Pounds (Instrument Only)
Power Requirements
6 to 55 Volts
Typical: 0.075 amps @ 28 Volts
Dimming
Auto (electric eye) and Manual
Environmental
DO-160G
Internal Storage
1,000 hours, RS232 port
Certifications
FAA TSO’d -C43c, -C44c, -C45b, -C47a, -49b, -C55a

[I chose EI because they offer a] certified replacement vs. back-up only and they look great.
The tach looks and operates amazing. Extremely accurate.
Keep it up. I’ll keep coming back.
The OPT-1 is more readable than the factory Cessna oil pressure/temp gauges.
We have other EI products currently and have always been satisfied.
Gauge works great! Very happy with purchase.
Great tech support. Someone always answers and gives accurate concise information.
Big improvement over old cluster (gauges). Good customer service.
Outstanding Customer Service!!
EI representatives… have been very helpful, truthful, and knowledgeable… We had no idea, that a few weeks later [after our purchase], we would need to have a Top Overhaul. What great timing! Having your engine monitor installed in our plane will hopefully help us keep it out of the shop for further engine repairs.
Incredible customer service.
Very accurate readings! The “analog” style LED arc means at-a-glance tach readings that allow the pilot to keep his attention where it matters, not reading a gauge. The digital readout is great for maintenance checks and mag drop tests.