ʻO kakāʻei kapuhe mea lako lako e hookui ana i ke kino o ke keena a me ka puka keena. Ua kapa ʻia ʻo ia he hinge huna. ʻO ia ka ʻāpana haʻahaʻa o ka puka keʻena a hoʻokani i ke kuleana o ka wehe a pani ʻana i ka puka keʻena. ʻO nā ʻano hinge lako he lima pololei, piko waena, a me ka piko nui. Hoʻokaʻawale ʻia nā puka ākea o ke poʻo kīʻaha hinge i 45mm, 48mm a me 52mm, a ʻo ke anawaena o nā puka he 26mm, 35mm a me 40mm. Hiki ke hoʻolako ʻia ke poʻo kīʻaha hinge a me ke kumu hinge me nā ʻano nui like ʻole o nā ʻāpana lāʻau a me nā wili ʻEulopa. ʻO nā mea hinge mea hale ka nui o nā mea hao a me nā mea kila kila. E like me kā lākou mau hana, ua māhele ʻia lākou i nā hinges buffer a me nā hinges maʻamau. He kūpono ia no ka hoʻohana ʻana ma nā puka lāʻau, nā puka aniani, a me nā puka puka alumini, me nā ʻano like ʻole. ʻO ke ʻano o ka hinge buffer ka lawe ʻana i kahi hana paʻa i ka wā i pani ʻia ai ka puka o ke keʻena, e hōʻemi ana i ka walaʻau i hoʻokumu ʻia e ka hui ʻana me ke kino keʻena ke pani ʻia ka puka o ke keʻena. ʻO ka hinge base he ʻelua puka, ʻehā puka, ʻekolu-dimensional hoʻoponopono o ka ʻokoʻa ma waena o ke kumu, hiki iā ʻoe ke koho mai nā ʻano koho.