Suitable method of affixing vehicle badge/decal onto vehicle

Fellows

What type of glue is used to fix vehicle badging permanently back in place ? (Permanent = firmly affixed long term, not falling off due to Sun / rain / car wash ).

The badging (single alphabets and numbers, metal, abt 15mm size each) was removed, now want to put it back.

Any tried/tested/trusted product, please let me know.

Much appreciated.

Thanks.