NJ E-Z Pass

E-Z Pass is an electronic toll-collection system.
It is normally a small box placed behind the rear-view mirror.
That transponder "tag" wirelessly identifies your vehicle to tollbooths to automatically pay tolls at participating highways
such as the New Jersey Turnpike, Garden State Parkway, bridges and tunnels.
Some crossings offer discounts to E-Z Pass users at certain times.

The New Jersey E-Z Pass can be obtained by mail or at selected Retail Locations.
Here is a map of all participating states
NJ, NY, PA, DE are among the 16 north-east states in The E-ZPass Group.
Your E-Z Pass is valid at all participating agencies.
Florida DOES NOT ACCEPT EZ PASS; their Sun Pass is an entirely separate system.

According to Wikipedia it is possible to get an E-Z Pass with no fees from certain agencies, without any residency requirement.
See the table of Fees and discounts by state to compare the fees.