Ọ bụ ezie na ha abụọ bụ "C" - ekara, obe ha - nkọwa ngalaba na ike nhazi dị nnọọ iche, nke na-emetụta ibu ha ozugbo - ikike ibu na ngwa ngwa.
Obe - ngalaba nke C Channel bụ ana-ekpo ọkụ - akpọrepu integral Ọdịdị. Weebụ ya (akụkụ kwụ ọtọ nke "C") dị oke (na-abụkarị 6mm - 16mm), na flanges (akụkụ abụọ kwụ ọtọ) dị obosara ma nwee ụfọdụ mkpọda (iji kwado ọkụ - nhazigharị). Nke a imewe na-eme ka cross - ngalaba nwere ike ekwe nguzogide na torsional rigidity. Dịka ọmụmaatụ, ọwa 10 # C (nke dị elu nke 100mm) nwere ọkpụrụkpụ weebụ nke 5.3mm na flange widths nke 48mm, nke nwere ike ibu arọ nke ala ma ọ bụ mgbidi na isi ihe owuwu.
N'aka nke ọzọ, a na-emepụta C Purlin site na mkpuru oyi nke efere ígwè dị mkpa. Obe ya - ngalaba bụ karịa "slim": ọkpụrụkpụ weebụ bụ naanị 1.5mm - 4mm, na flanges dị warara ma na-enwekarị obere mpịachi (a na-akpọ "ọgịrịga na-agba ume") n'akụkụ. Emebere ọgịrịga ndị a na-agba ume iji melite nkwụsi ike mpaghara nke flanges dị mkpa ma gbochie nrụrụ n'okpuru obere ibu. Agbanyeghị, n'ihi ihe dị gịrịgịrị, nkwụsi ike nke C Purlin n'ozuzu adịghị ike. Dịka ọmụmaatụ, C160 × 60 × 20 × 2.5 C Purlin (ịdị elu × flange obosara × ịdị elu webụ × ọkpụrụkpụ) nwere ngụkọta ịdị arọ nke naanị ihe dịka 5.5kg kwa mita, nke dị mfe karịa chanel 10 # C (ihe dị ka 12.7kg kwa mita).