Colorado Head Office
National Interlock Service (CO) Ltd.
1660 Jasper St. Suite "I"
Aurora, CO 80011
toll free: 1-800-475-5490
phone: 303-361-0194
fax: 303-361-0930

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Delaware Head Office
National Interlock Service (DE) Ltd.
420 Market St.
Bridgeville, DE 19933
toll free: 1-800-833-8199
phone: 302-337-9702
fax: 302-337-9602

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Illinois Head Office
National Interlock Service (IL) Ltd.
8509 W 191st
Mokena, IL 60448
toll free: 1-800-508-4794
phone: 815-464-0907
fax: 815-464-0908

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Indiana Head Office
National Interlock Service (IN) Ltd.
toll free: 1-866-324-6392

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Maryland Head Office
National Interlock Service (MD) Ltd.
Chesapeake Plaza
8328 Veterans Highway
Millersville, MD 21108
toll free: 1-800-374-5760
phone: 410-987-4266
fax: 410-987-4265

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Michigan Head Office
National Interlock Service (MI) Ltd.
12409 Stark Rd.
Livonia, MI 48151
toll free: 888-294-7002
phone: 734-367-1070
fax: 734-525-4171

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Montana
National Interlock Service (MT) Ltd.
922 1st Ave. N.
Great Falls, Montana 59401
phone: 406-453-6784

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New Jersey Head Office
National Interlock Service (NJ) Ltd.
toll free: 1-800-475-7151

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New York Head Office
National Interlock Service (NY) Ltd.
1557 Lincoln Avenue.
Holbrook, NY, 11741
toll free: 1-800-871-5462
phone: 631-580-3090
fax: 631-580-1291

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Oklahoma Head Office
National Interlock Service (OK) Ltd.
3424 Lakeside Dr.
OK City, Oklahoma, 73179
Phone: 405-685-2522
Fax: 405-685-8501
Toll Free: 1-800-743-0373

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Pennsylvania Head Office
National Interlock Service (PA) Ltd.
3200 Pike Street
Harrisburg, PA 17111
toll free: 1-866-342-4984
phone: 717-558-9184
fax: 717-558-9188

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Texas
National Interlock Service (TX) Corp.
12783 Capricorn-Suite 900
Stafford, TX 77477-3978
toll free: 1-866-863-4350

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West Virginia Head Office
National Interlock Service (WV) Ltd.
1221 Pennsylvania Ave.
Charleston, WV 25302
toll free: 1-877-753-6571
phone: 304-343-1625
fax: 304-343-1630

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To order an application for the Alcohol Test And Lock Program, call the Department of Motor Vehicles, Toll Free 1-800-642-9066

Wisconsin Head Office
National Interlock Service (WI) Ltd.
1051 Tower View Drive, Unit K
Greenville, WI 54942
toll free: 1-800-584-1226
phone: 920-757-0962
fax: 920-757-0964

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