I'm a Clifford fan, but both Viper and Clifford are now owned by Directed so some of the accessories available might be interchangeable. Check the list of the available accessories for each and you will find what you are looking for, and then choose the level of system you want add your chosen accessories to:
One of the best accessories I have ever had installed is the Clifford BlackJax, but it can be real pain as valets never seem to get the clue and always play with the switch after being told not to. I have been interrupted during many a meal by an embarrassed valet as I have had to go stop my car from the alarm going off, and it being stopped dead in its tracks. The best was in the middle of the parking ramp blocking both the ingress and egress lanes. (Wonder why he was driving in the middle
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