Rated Bow Shackles from 0.75t to 3.2t
Rated bow shackles are accepted to use in place of a dee shackle.
A Bow shackle is a superior device to a dee shackle. The bow shackle spreads the snatch strap load more evenly in the bow.
Can you use a tow hook for caravan safety chain?
Catch 22 Myth
If someone says, "Your shackle does not need to be rated, ask them how they prove to the Police that the shackle is comparable to the safety chain.
Trailers over 2.5t must have two safety chains; each chain must have the same capacity or exceed the ATM.
Trailers Under 2.5t
If your trailer does not exceed 2.5t ATM, it must have one safety chain complying with AS 4177.4-1994.
Australian Standard AS 4177.4-2004 'Caravan and light trailer towing components – Part 4.'
Trailers 2.5 to 3.5t
If your van is over 2.5 tonnes and under 3.5 tonnes ATM, it must have two safety chains of 3500 kg for each chain.
Trailers Over .5t
According to Standard AS 4177.4-1994 and Australian Standard AS 4177.4–2004, trailers over 3.5 tonnes ATM must have two safety chains made from steel of a minimum 800 MPa breaking stress.
Also, shackles over 5t conform to the mechanical properties of the Grade-T chain as specified in Australian Standard AS 2321-1979. 'Short Link Chain for Lifting Purposes (non-calibrated), or Australian Standard AS 2321–2006 Short Link Chain for Lifting Purposes.
Ultimately, you'll need to go in for a chain sized such that the minimum breaking load or braking capacity exceeds the ATM by 1.5 times.
Rated Bow Shackles connect your safety chain to your tow vehicle and can handle the rated load.
Find Tasmanian Guidelines here. Guidelines are approximately the same in every state.