He polyethylene kiʻekiʻe ke kiʻekiʻe o ka papa o loko, ʻo ka ʻāpana o loko i hoʻohana i kahi mea hoʻonaninani haʻahaʻa haʻahaʻa silica gel solid lubricant. ʻO ia ka pale ʻana i ka corrosion, ka paia i loko maʻemaʻe, ka hoʻouna ʻana i ke kelepona puhi ahi kūpono, a me ke kumu kūʻai haʻahaʻa. E like me nā pono, ʻokoʻa nā ʻokoʻa a me nā kala o nā paipu liʻiliʻi e ka casing waho. Hoʻohana ʻia nā huahana i ka ʻōnaehana kelepona kelepona optical no ke ala kaʻa, kaʻaahi a pēlā aku.