Dhuumaha birta ee saxda ah waa nooc ka mid ah alaabada birta saxda ah ee saxda ah kadib sawir qabow ama duubid kulul.Sababo la xiriira faa'iidooyinka lakabka oksaydh lahayn ee derbiyada gudaha iyo dibadda ee birta saxda ah, ma daadanayo cadaadis sare, sax sare, dhammayn sare, ma qallafsanaan inta lagu guda jiro foorarsiga qabow, ballaarinta lahayn, fidsan iyo dildilaac lahayn, waxaa inta badan loo isticmaalaa in ay soo saar qaybo pneumatic ama haydarooliga ah, sida dhululubada hawada ama dhululubada saliidda, kuwaas oo noqon kara tuubo aan xidhnayn ama tuubo alxan leh.