![]() Perno Hexagonal  | 
			![]() Tuerca Hexagonal  | 
			![]() Perno en U  | 
			![]() Arandela Elástica  | 
		
![]() Tornillo de Cabeza Hueca Hex  | 
			![]() Varilla Roscada  | 
			![]() Perno Prisionero  | 
			![]() Arandela Plana  | 
		
| Grade | UNS | C≤ | Mn≤ | P≤ | S≤ | Si≤ | Ni | Cr | Cu | Mo | 
| Alloy 31 | N08031 | 0.015 | 2 | 0.025 | 0.01 | 0.3 | 30.0-32.0 | 26.0-28.0 | 1.0-1.4 | 6.0-7.0 | 
| Mechanical properties | Tensile, min, ksi[MPa] | Yield, min, ksi[MPa] | Elongation, %(min) | 
| Alloy 31 | 94[650] | 40[276] | 40 |