Has 90 Degree rubber boot 16mm diameter, two zip ties and foam filter. Fits most .21 or engine with a 13-15mm in take (like the new Traxxes TRX 2.5).Over 5.3 Sq in of air flow area.(Stock Traxxas air filter TRA5260 3.77 sq in air flow area)(Stock HPI87044 air filter 3.1 sq in air flow area)Best use with Team Associated Foam Filter Treatment. ASC7710
