Raws li ob txoj kev pob khawm, nres nres ntawm 45 thiab 110 degree, tom qab 45 degree tsis kaw thiab 15 degree me me-lub kaum sab tsis kaw tag nrho yog nws qhov txiaj ntsig zoo.
Lub rooj tog kho vajtse pob khawm yog ib hom hlau tivthaiv uas tso cai rau lub qhov rooj lossis lub hau kom viav vias qhib thiab kaw ntawm ib qho rooj tog. Nws yog ib qho tseem ceeb ntawm cov rooj tog tsim thiab kev ua haujlwm.
Cov hinges no muaj qhov yooj yim thiab intuitive tsim uas tso cai rau yooj yim txuas rau koj cov rooj tog zaum, ua rau lawv zoo tagnrho rau cov neeg uas xav tau sai sai sib sau lawv cov rooj tog hauv tsev.