Strength classes / Tensile load

TWINNUT nuts from vending machines and stainless steel typically achieve the strength class 8. The use of tempered steel can also be the strength class of 12 or more can be achieved.
In a nut M12, this corresponds to a tensile load of 10 tons. TN934-M39 steel nuts have been tested with more than 50 tons of tension.
The TWINNUT-nuts Grivory also achieve very high strength values. A M12 Grivory TWINNUT type TN6331 carries about 2 tons burden, and this with only 22% of the weight of an equal-sized steel nut.