The number of GM vehicles rocking OnStar remote assistance technology will increase from 1.4 million in 2004 to 3 million in 2006. OnStar provides air bag deployment notification, remote door unlocking, stolen vehicle locating and remote vehicle diagnostics on cars ranging from low-priced Chevys to luxed-out Caddys. OnStar was introduced in 1996; it is standard on all Hummers and Cadillacs, and a $700 option on many other GM vehicles, with subscription after the first "free" year running about 17 clams a month. An OnStar spokesman said that the retention rate after the first year is 60 percent. As a GM subsidiary, OnStar-style equipment can also be found on models from Lexus, Acura, Audi, Saab, Subaru, Isuzu and VW.