In today's economy it's important to get the most you can for your buying dollar. So there's no rationale to over pay for Car Adapter Power when there are such a huge amount of them for sale on eBay. Plus, eBay is one of the biggest and most trusted online shopping sites in the world. This site is authorized by eBay to help you find the Car Adapter Power you are shopping for and show them to you. If you don't see the Car Adapter Power you are hunting for below. Use the search feature on the right to find the variety you want.
How does the power adapter(cigarette lighter) work in the car? Are the walls of it (-) and the prong (bottom) (+) or other way around?
One more question, I have a light that requires 12V power which is then ran into a transformer to turn it into whatever the light needs, dealing with the 12V would it be okay to wire up (2)9volt batteries side by side and run them to the transformer? If I do so what kind of wiring would be required? Thanks
dogmabites, thanks man. It worked! Just some stupid little neon light. Ill vote you best answer as soon as it gives me the chance 
Tip is positive, side is negative.
For using batteries, if you connect two 9V batteries in series, not parallel you will provide 18 VDC to the device. It will provide a voltage 50% higher than normal to the bulb. I'm not sure if this will harm the bulb or not. To connect in series, connect the positive of one battery to the negative of the other. Now, the free positive of one battery is 18V higher than the free negative of the other.
How harmful it is depends a bit on what it does with the 12 V. If it sends the 12V directly to the bulb, it wont hurt too much, just reduce the life of the bulb. If it is going through a power inverted (converting it to 120 AC), then you will be generating unsafe voltages.
Unless it is a small light, a plain 9V battery will not provide enough current to power it. It can supply 9W for about 1/2 hour. The two together would be 18W. (If you consume less power, you get proportionally more time).
5000w pure sine wave power inverter 12vdc/110vac 60hz converter transformer tool, 10000w power inverter 12vdc/110vac 60hz converter transformer power tool RV car, Universal Dual Port USB AC Car Charger Adapter two ports 1A 1000 mA output White, Car Parking Reverse Backup Radar 4 Sensor Assistance System Alarm Buzzer Silver, Sony Xplod XM-ZZR3301 600W Mono Class-D Car Audio Amplifier, High Quality 220V 1000W USB Car Power Inverter DC to AC New Adapter, 4.3" Car GPS Navigation FREE 2GB Maps Stereo Headphone , Nextar X3i 3.5-Inch GPS Navigator Bundle AC & DC Adapter Face Plates - NEW , NEW BOSS CE2004 EPIC 2000W 4 Channel Car Audio Amplifier Power Amp MOSFET Stereo, BULLZ AUDIO EPAK4BL 4 Gauge Amplifier Amp Wiring Kit + 2.2 Farad Power Capacitor, CAR DC POWER ADAPTER CORD FOR TOM XL 340 S 340S LIVE, BULLZ AUDIO BPG0.50BK Car Audio 1/0 Gauge 50 FT Power Wire Ground Cable - Black, Car Power Adapter Charger Cord for IZZO SWAMI GOLF GPS, FORD MUSTANG 05-12 COUPE KICKER CAR DUAL 12" ZX750.1 LOADED SUB BOX PACKAGE, 4) New BOSS CH6500 6.5" 2-Way 400W Slim Car Speakers, KICKER AUDIO CAR 4X6" SPEAKER PACKAGE (2) KS460 NEW, All in one radar laser detector 7inch GPS USA MAP, DC 12V to AC 220V USB Power Inverter w Universal Socket, Car Steering Wheel Bluetooth Adapter with FM Modulator + MIC , H1031 6.2inch in dash
car dvd player gps navigation for bmw 3 series, Wagan 12V Heated Car Seat Cushion Hi/Low Heats Off Switch, KICKER PACKAGE (2) CVT10 SUBS, DUB2802 AMP & TRUCK BOX, 2pcs 194 168 501 T10 5-SMD White 5050 LED Car Light Bulb, 1x White 39mm 1210 16-LED Festoon Dome LED Light Bulb, 3 in1 DC Power Car Charger Adapter Splitter + USB Port, 2) NEW KICKER DS65 6.5" 200 Watt 4-Ohm 2-Way DS Series Car Audio Speakers 11DS65, Black Car MPV SUV Vehicle LED Display 4 Parking Sensor Reverse Backup Radar Kit, HIGH POWER Mini FM Car Bike Boat PC MP3 CD Speaker HIFI Audio Amplifier AMP NEW, Garmin Rino 655t Handheld GPS Navigator, Garmin Rino 650 Handheld GPS Navigator, Garmin nüvi 2300LM Automobile Portable GPS Navigator, Garmin nuvi 2370LT Automobile Portable GPS Navigator, Joutec Teye Police Taxi Vehicle Drive Dual Video Cam - GPS, Speed, 4GB storage, KICKER® 10-CVT8-2 8" CompVT SHALLOW MOUNT SUB WOOFER CVT 2-OHM 200W RMS 10CVT82, 4) NEW BOSS MR60B 6.5" 2-Way 400W Marine Speakers Black, Evesham Nav-Cam 7000 USA, Cobra CJIC 250 100 Watt Portable Jump-Start/Air Compressor ~AC & DC Power Outlet, Magellan Roadmate 1400 1412 1430 1200 1212 Car Charger Vehicle Power Adapter, NAXA NX-671 CD/AUX/AM/FM In Dash Car Audio Radio Player, Kenwood KDC-BT652U In-Dash USB Car Stereo Receiver w/ Bluetooth KDCBT652U , 5M 300 LED SMD 3528 Waterproof(IP65)Flexible/DIY Cut-able Light Strip(Day White), NEW! 2) PYRAMID 312SX 3.5" 100 Watt Car Audio Speakers, HOME WALL AC +CAR CHARGER FOR GARMIN NUVI 250W 265 1300, NEW 12V V 3 CHANNEL 2.1 Subwoofer Digital Amplifier Car, BNIB Vector iMobile 100 Watt Slim Power Inverter DC to AC provides 110Vac , All in one radar laser detector 7inch high digital GPS , Magellan Roadmate & Maestro GPS FREE Lifetime Traffic Link Charger AXRDS1SXXUC, KICKER SUBWOOFER PACKAGE (2) CVT10 SUBS & TRUCK SUB BOX, INFINITY 1260W Reference 300 Rms 1200 Watts 12" 4OHM Car Audio Subwoofer Sub , 7''TFT touch screen with 1677pixels, 800*480 resolution, 2) New BOSS CH4630 4"x 6" 3-Way 500W Car Audio Speakers, Pioneer AVH-P2300DVD Double-DIN DVD Receiver, Portable Mini Golbal GPS Tracker GPS GPRS GSM Tracker for Pet Kids Car Safety, NEW Rockford Fosgate PEQ Remote Bass and Treble Knob , 2 PAIRS HIFONICS 850W 6x8 3 WAY CAR STEREO SPEAKERS NEW, KICKER CAR AUDIO SUBWOOFER PACKAGE (2) CVT10 SUBS NEW, KICKER CAR AUDIO SINGLE 12" VENTED SUB BOX ENCLOSURE CVT12 ZX400.1 AMPLIFIER, Sylvania 4.3-Inch GPS Navigation System --AS IS--, TomTom XXL 540 Automotive Portable GPS Navigation System Receiver, BULLZ AUDIO 1/0 Gauge 50 FT Power Wire Ground Cable Red,
