Understanding Safety Chains can be difficult and confusing. The experts at Couplemate have tried to make it simpler with this animated video.

Someone said to me the other day that Rated Dee Shackles was not a Government requirement anywhere in Australia. I replied, check N.T. last time I looked it was legislated.

The real question is, how do you prove your gear is safe unless it is stamped?

Trailer Side Safety Chain With Hammerlock and Holder.
One set to suit trailers up to 2.5t
Trailers over 2.5t require two sets.
Galvanised Chain and shackles are illegal on all trailers over 3.5t.

It is essential to remember
No chain welding over 2.5t
No chain welding below the chassis rails.
Trailers up to 2.5 tonnes ATM must have at least one safety chain complying with AS 4177.4 – 1994 (Trailer and light trailer towing components – Safety chains up to 3.5 tonnes capacity), or as amended from time to time. This standard allows for steel safety chains by the following:

up to 1.0 tonne, a chain size of 6.3 mm;
up to 1.6 tonnes, a chain size of 8 mm;
from 1.6t to 2.5t, a chain size of 10 mm.
Trailers over 2.5 and up to 3.5 tonnes ATM must have two safety chains complying with AS 4177.4 – 1994 or as amended from time to time. This standard allows for steel safety chains by the following:

up to 3.5 tonnes, a chain size of 13 mm.
However, trailers

more than 3.5 tonnes ATM,
all medium and heavy category pig trailers with rigid drawbars,
any other trailers without breakaway brakes
and all fixed and rigid pig trailers with a GTM greater than 2.5 tonnes and fitted with automatic pin type couplings,

Must be fitted with safety chains.

Link do Vídeo