What the standard defines
The smaller of the two sockets is specified in a DIN document that fixes its diameter and contact arrangement, which is why plugs from different makers fit reliably. The wider cigarette-lighter socket has no single publisher: its dimensions are a trade convention inherited from an accessory that no longer exists on most vehicles.
What each product publishes is a current rating, and that is the figure that matters. It belongs to the socket, and it assumes wiring and a fuse sized to match.
What it does not promise
The shape says nothing about the current available. A socket wired with thin cable behind a 10 A fuse delivers 10 A whatever its diameter, and an adapter between the two shapes changes nothing upstream.
It also says nothing about whether the socket stays live with the ignition off — a detail that decides whether a solar trickle charger plugged into it works at all, and which varies by vehicle rather than by socket.
What it works with
These sockets appear on power stations, battery boxes, vehicles and cool boxes across this site. Where a maker publishes a current rating and a fuse size, the product page reports both; where a product is sold as an adapter, the product page says which shape it converts and notes that the rating is set elsewhere.
What people ask before they order
Can I plug a DIN plug into a cigarette-lighter socket?
Not directly — the diameters differ. Adapters exist in both directions, and they change the shape without changing what the wiring and the fuse behind the socket will carry.
How many amps can a 12 V socket take?
It depends on the socket, the wire and the fuse, not on the shape. Ten to twenty amps is the usual range, and the maker publishes the figure for each product.
Last reviewed 16 September 2026