The thread on this type of nut can often (but not always!) be identified by the colour of the nylon insert, with blue signifying metric and white for imperial threads. For further information please take a look at our guides and tips section.
Flanged Nyloc nuts are also available, please click on the link to view the range.
A Type T nyloc nut is a thin type of nyloc nut and should be chosen if the nut is going to be installed in a restricted space.
About Metric A4 Stainless Steel Nuts
A4 Stainless is often referred to as 316 or 18/10 stainless. As in A2 above, the numbers 18/10 refer to the chromium and nickel content- 18% chromium and 10% nickel.
A4 stainless is often used in marine or chemical environments as it has greater corrosion resistance than A2.
The chemical composition of both A2 and A4 stainless steel are almost identical with the most notable differences being the higher nickel content and the addition of Molybdenum in A4. Molybdenum is a silvery white metal that is highly corrosion resistant, very ductile and has an extremely high melting point.
There can also be Titanium present in A4 stainless at the option of the manufacturer.
Typically, A4 grade stainless steel costs slightly more than A2 because of its enhanced chemical and production properties. The extra cost can be justified, however, because hardware made of A4 stainless steel is extra resistant to tarnish and corrosion, enabling it to last a very long time.