U post. Ibyobo byakubiswe byonyine byanditse byerekana neza ko bifatanye neza nuruzitiro. Irashobora rero gukoreshwa mukurinda uruzitiro rwinsinga, gutunganya ibihingwa, ndetse no kurinda umutekano wumuhanda, nibindi.
Inyandiko za U zishobora gushyirwa muburyo bubiri: hamwe na spade cyangwa idafite spade. Isuka yasuditswe neza kuri post ifasha kongeramo uruzitiro mukwongera aho uhurira kubutaka. Inyandiko idafite isuka irashobora koroha cyane inyundo mu butaka kuruta iyo ifite isuka.