Inguni yunamye kuri iyi ni dogere 90 kandi iraboneka mubunini bwa 14mm.
Ongera usubire gufata, nkuko byumvikana, gufata no gukusanya ibumoso hejuru yo kwisubiraho kugirango ufate dab kugirango ubashe gukoresha ibumoso hejuru yibikoresho kimwe no kugira isuku ya dab yawe.