How many letters does the top answer for “pneumatic tire not needing an inner tube to be airtight” have?

The most common answer is tubeless (8 letters).

Crossword clue: pneumatic tire not needing an inner tube to be airtight

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

tubeless 8 letters wn-def

pneumatic tire not needing an inner tube to be airtight

of a tire; not needing an inner tube 71% similar → tubeless