It sounds to me like he was trying to sell you the Triad security system which dealers install to protect their lot.
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It is a wand type device that you must put near the antenna (usually near the light) that will allow the vehicle to start.
Sound familiar?
I just purchased a new Chevy Avalanche and the finance guy tried to
> sell me an alarm. He said the retail price was 599 but he would let me
> have it for 399. I refused and he came down to 268. The dealer already
> installed it on the vehicle. There was a Red LED below the steering
> wheel. When I refused it they took it out. I am sure he was probably
> trying to sell me something I could probably get very inexpensively > online.
>
> The Avalanche comes with an alarm that is activated when a door is
> open. I think this was probably just adding a shock and glass break
> sensor to the built in alarm.
>
> Does anyone know what he was trying to sell me and if it can be
> purchased for a fraction of the cost?
>
> Thanks,