What Does It Mean When Chain is Described As Being 30 or 43 Proof

Question:

What does the number mean......30 proof 43 proof???

asked by: Gary

Helpful Expert Reply:

Using the term 'Proof' when describing chain is a descriptor of its weight rating and its construction.

A grade 30 or 30 proof chain is for a general purpose application that doesn't require a great amount of strength. A grade 30 chain will have a working load limit from 1300-6900 lbs, and is constructed of low-strength carbon steel.

A grade 43 or 43 proof chain would be the next strongest grade, constructed of carbon steel with a working load limit of 2600-13000 lbs which makes it ideal for towing or for a safety chain like the Buyers Products # 337BSC3835 safety chain you'd looked at. Two of these chains be great for a trailer weighing up to 15000 lbs.

I've linked to a product description video that you might find helpful.

expert reply by: Mike L