Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Does not work with the Garmin eTrex Venture CX

When I purchased this I thought it would work with the Garmin eTrex Venture cx that I purchased at the same time. Well I was wrong. I had to purchase a iGo unit from Radio Shack to power this while in the car. The iGo unit worked very well while we drove from MN to CA.