What's the best way to mark your gear ?

I've tested the classics solutions like electrical tape or nail polish but i'm looking for better solutions.

First, the tape worn quickly, let glue stain the carabiners when it's too warm outside.

The nail polish is also not so durable, particulary on modern gear where all is laser engraved and no asperity let the polish nail dig in.

Out of my mind this week i've think of thermo-rectractable sleeve of electricians. Somes of you guys already tested it ? Or another solution ?