Looska siman- madaxa ayaa leh qayb cylindrical siman ama toosan. Looska jeexjeexan ee si toosan loo jeexjeexay ayaa caadi ahaan loo isticmaalaa inta lagu jiro wax soo saarka sababtoo ah jeexjeexyadooda tooska ah waxay bixiyaan saameyn liddi ku ah simbiriirixiinta. Qolka siman-Madaxa lowska madaxa wuxuu ka soo baxaa biraha birta ah inta lagu jiro qulqulka. Flat{6}} lowska madaxa ayaa sidoo kale ah nooca ugu badan ee la isticmaalo uguna waara ee lawska rivet.
Midka loo yaqaan 'countersunk head rivet nuts' sidoo kale wuxuu leeyahay dhammaystir siman ama toosan. Waxay u jeexeen go'yaal dhuuban oo leh chamfers. Ka dib marka la rakibo, dusha sare ee madaxa ayaa la mid ah dusha xaashida. Agabka la heli karo waxaa ka mid ah birta galvanized, 304 birta aan daahin, iyo 316 bir ah.
lowska madaxa countersunk yar yar ayaa laga heli karaa birta galvanized, 304 ahama, iyo 316 ahama. Sida magacu soo jeediyo, lowska madaxa countersunk yar yar ayaa leh dhexroor madax ka yar iyo dhumucdiisuna tahay marka loo eego lowska rivet madaxa. Haddii biraha xaashida ahi ay dhuuban yihiin oo chamferku yar yahay ama maqan yahay, lowska yar ee madaxa countersunk ayaa ah ikhtiyaarka kaliya.