He pahu pahu quad aka aka ma'alahi keia. ʻO ke anawaena o kēlā me kēia pahu i loko he 25mm. Alohilohi ka poʻi a me lalo, a he mea hōʻoluʻolu ke nānā aku. ʻO kona ʻokoʻa, ʻoi aku ka lahilahi ma mua o ka nui o nā disc aka maka, he 11mm wale nō ke kiʻekiʻe, a ʻoiai he huinahā, aia nā radians kona mau kihi, no laila ʻoi aku ka maikaʻi.