Does the input polarity matter for a 12V DC adapter? - Electrical Engineering Stack Exchange
CERRXIAN 12/24V Female Car Cigarette Lighter Socket Plug Connector DC 5.5mm x 2.1mm to Female Cigarette Socket Car Charger Cable Adapter : Amazon.co.uk: Electronics & Photo
Barrel Connector to Cigarette Lighter Socket Adapter
Universal 15a Portable Cigar Style Car Cigarette Lighter High Temperature Cigarette Lighter For Car Auto Interior Parts - Cigarette Lighter - AliExpress
ResMed S8 12VDC POWER CORD Direct to your Cigarette Lighter Socket -- 5YR WRNTY 790566655300 | eBay
12V 5A (60W) car/caravan cigarette lighter socket DC adapter for LCD TVs, LCD monitors, and other equipment. Input: DC 12V ~ 30V. Output DC 12V, 5A (MAX), 1 year warranty: Amazon.co.uk: Automotive
Panel Mount Cigar Lighter Power Socket | 12 Volt Planet