Ƙofar zamiya ta kasuwanci ta WJW sabuntawa ce ta Ƙofar Sliding ta Kasuwanci wacce ke nuna sabbin sassan sill na Biyu da Biyu Track da adadin sabbin zaɓuɓɓukan sash waɗanda ke ba da izinin gilashin kauri, glazing sau biyu da zaɓin glazing akan shafin.
Manyan canje-canjen sun haɗa da sabbin sassan sill tare da faɗuwar waƙoƙi waɗanda za a iya maye gurbinsu cikin sauƙi idan lalacewa ko sawa kuma ƙirarsu ta musamman ta rufe ramukan magudanar ruwa mara kyau a cikin sills tare da ƙarin fa'idar ƙara aikin ruwa. Duk sills da ke akwai suna ci gaba da kasancewa don aikace-aikace inda ba a amfani da ƙaramin sill.
Gutter sills a cikin nau'ikan waƙa biyu da sau uku yanzu ana samun su don aikace-aikacen sill ɗin da za a iya cirewa kuma waɗannan sun haɗa da aluminium, ko grate bakin karfe don matse ruwan saman.