Ibisanzwe bikoreshwa byerekanwa bifite ubwoko bubiri: ubwoko bwa flange, nubwoko bwa kare. Iyambere ni hepfo gato , ariko iragutse cyane, kandi umwobo uzamuka ni umwobo uhujwe, mugihe uwanyuma ari muremure gato kandi muremure, kandi umwobo uzamuka ni umwobo wimpumyi. Byombi bifite ubwoko bugufi, ubwoko busanzwe nubwoko burambuye, itandukaniro nyamukuru nuko uburebure bwumubiri wigitambambuga butandukanye, byanze bikunze, intera yumwobo wurwobo rushobora no kuba itandukanye, ubwoko bwubwoko buto bugufi bufite ibyobo 2 gusa.