Unfortunately autogas connectors around the world aren't all the same. Even in Europe there are four different ones (ACME, Bayonet, Dish, Euro). You can read more about each of them and which country has which one on this page - LPG connectors and adapters
Here is a list of places where you can buy lpg adapters:
LPG stationsBigger stations or stations with greater frequency of visitors tend to sell or even lend the most used adapters. If you are only passing a country and won't need that adapter after, it is a possible alternative to find one of those stations and tank there. But please, contact them directly beforehand to check if they have the right adapter to lend.
Garages that are specialised in servicing LPG systems or converting vehicles to LPG usually sell adapters. It is highly recommended to call and ask them before driving to their location. Smaller garages that convert or service LPG systems only as an additional service tend not to have all the adapters available, if any.
There are quite a few internet stores that sell all possible accessories for your LPG powered vehicle, including different adapter combinations. One of them is also Amazon.
If you do not know what size adapter thread you need, then you can find out the size by measuring the thread of the plastic cap of your filler.
Gomet LPG GPL Autogas Tank Refill Adapter Set M10 for All Europe ACME DISH EURONOZZLE BAYONET with Bag
ACME Tank adaptor 10 MM / M10 Short Brass LPG, LPG / GPL
DREHMEISTER ACME filling point adapter 10mm / M10 long version
Car Auto Gas Tank Adaptor Kit in Europa (Acme, Dish, Bayonet) LPG Gas 12 mm Short
Tank Adapter - Europe (Acme Boot Dish, Bayonet) LPG Auto Gas 12 mm Long
Tank Adapter - Europe (Acme Boot Dish, Bayonet) LPG Auto Gas 14 mm Long
Tank Adapter - Europe (Acme Boot Dish, Bayonet) LPG Auto Gas 16 mm Long
Gomet LPG GPL Autogas Tank Refill Adapter Set M22 for All Europe ACME DISH EURONOZZLE with a Bag RHT
Gomet LPG GPL Autogas Tank Refill Adapter Set M22 for All Europe ACME DISH EURONOZZLE BAYONET with Bag
DREHMEISTER ACME onto DISH filling point adapter
ACME filling point adapter Ø22mm (1 ¾ x W 21,8) short version LPG UK to EUROPE
Autogas LPG Filling Point Adapter UK Bayonet (W21.8) to DISH
Dish (M10) to EURO Connector Adapter
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