This is a replacement hinge for the support bars on the "Winged Clothes Airer with Garment Rack" SKU: P_42115397 purchased from Kmart Australia. https://www.kmart.com.au/product/winged-clothes-airer-with-garment-rack/635857
I found the hinges are very thin plastic which easily failed when used outside with a bit of wind.
To replace the part, you need to remove the old hinge by pulling out the two tubes that it is attached to and sliding off then replace with the new one. You may want to use a little adhesive to secure it in place, but a press fit is fine - this is how the whole product is typically assembled anyway.
I also noticed that the clip used to secure hold the support bar in place will have an impact if it isn't centered so I'll be adding an additional clip to allow one to be used on each side.