After a full IFR install on my Cessna 175, my two favorite instruments without question is the CGR-30 Combo set. Simple and customizable, the data is invaluable!
S-300 External Shunt
FAA Approved Accessory
- PMA’d
- 300 Amp
- 3.25″ (W) x 1.75″ (D) x 1.75″ (H)
- 11.5 Oz Unit
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Product Overview
Prices
Retail Prices
Package includes:
- S-300 Shunt
- Installation Instructions
Description
Package
Retail Price
S-300 External 300 Amp Shunt
S-300
$60

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Documents & Manuals
Testimonials
Customer Testimonials
Safety and simplicity!
- Customer
Andrew L. from Florida
- Aircraft
Piper PA-28-235 Cherokee Pathfinder
- EI Instrument
Responsive customer service, kudos to [customer service].
- Customer
James A. From Alabama
- Aircraft
Cessna 182B Skylane
- EI Instrument
Great Product, that provides a lot of very helpful engine data in an easy to use and see display! We are already finding cylinder cooling issues that we would’ve never known about before, and probably explains why we’ve had to replace that specific cylinder in the past. EI customer service on questions on how we wanted to set ours up was very helpful and positive. The CGR-30 had quite a few positive reviews online from other users.
- Customer
Ryan O. from North Dakota
- Aircraft
Cessna 182D
- EI Instrument
I won a FP-[5]L and had it installed in my c150. I was/am impressed with the accuracy and ease of operation of the FP. I wanted a new tach and I trust (and verified) that the EI R-1… would be my best choice. I am not a rich man. These instruments are affordable and incredibly accurate. Already planning my next buy from EI.
- Customer
Charles M. from South Dakota
- Aircraft
Cessna 150F
- EI Instrument
This is the third EI instrument I am having installed in “Lillybelle .” I am impressed with the ease of operation, the affordability and the accuracy of each of these instruments. For years I trusted my life to 50+ year old gauges. Now I don’t have to. What a relief!
- Customer
Charles M. from South Dakota
- Aircraft
Cessna 150F
- EI Instrument
Met all my requirements; great support.
- Customer
James Q. from Texas
- Aircraft
Falco F8L
- EI Instrument
The equipment is fantastic, very intuitive, and easy to use.
- Customer
Gregory S. From Brazil
- Aircraft
Air Tractor AT-502A
- EI Instrument
Great Service.
- Customer
Flying Academy from New York
- Aircraft
Piper PA-28-161 Warrior
- EI Instrument
We’ve worked with EI for years and love the product and support always received. Quality & dependability.
- Customer
Tammy B. from North Carolina
- Aircraft
Air Tractor AT-802
- EI Instrument
I really appreciate the quality of communication about my order. The instrument offers the right functionality (being a primary instrument) in the right form factor for my application.
Very easy to install and directions were straight-forward.
- Customer
Paul H. from Oklahoma
- Aircraft
Piper PA-28-151 Cherokee Warrior
- EI Instrument