best FM transmission for 99 Pontiac Grand AM?

[blkyu728]

I got 99 pontiac grand am recently, and tried to use FM transmission that i owned. I have two kinds, but none of them worked. I don't know why they aren't working. I'm just wondering if I need to buy specific brands of FM transmitter for Grand AM.

The brands I tried were Monster and Griffin.

 

[AmigaJoe]

Type of car doesn't matter at all. Just make sure frequency of transmitter matches what the radio is tuned to.