Question about Wing Nuts (Metric)?

Question

What does "32 mm" in an M5 x 32 mm wing nut refer to?

I have purchased an assortment of Wing Nuts from eBay that covers various sizes. Two of the sizes are M5 x 24 mm and M5 x 32 mm. What would the difference be exactly? Both of them have a diameter of 5 mm (I have measured them with a metric ruler)...

Thanks!

R.C.

Answer 1

32 refers to the pitch of the thread.  

The equivalent example in Imperial units is, for example a 1/4-20 vs. a 1/4-28 bolt.  Both are 1/4 inch in diameter, but the 28 has a finer thread (more threads per inch in this case).

Answer 2

The first number refers to the diameter of the bolt and the second number refers to the pitch. The pitch is calculated as the distance between any two threads.

An M5 bolt will have a pitch of .8 mm. There is no other pitch used for an M5 bolt. The 24 or 32 would refer to the length of the bolt in mm. from the underside of the head to the tip. Not sure how this would apply to a "wing nut" which is a nut that is made to be removed without the help of a wrench.