Raws li ib qho ntawm feem kev sib tw dai ntawm lub tuam txhab, peb cov yas 90 ° kev ncua ntawv clamp fasteners yog UPC pom zoo. Thiab lawv tau txais ntau lub npe nrov thoob plaws ntiaj teb, tshwj xeeb tshaj yog Asmeskas North. Tsis tas li, lawv cov pob txha pub rau cov yeeb nkab txhuam kom yooj yim dua thiab ntau ntsiag to thaum cov yeeb nkab nthuav dav thiab sib cog lus qauv.