Contact Bushman directly (I've always found their staff very helpful and knowledgeable) or call/visit one of their South Australian DC fridge stockists:

BUSHMAN Portable Fridges 

3 Contour Close
Research VIC 3095 

03 9437 0737
info@bushman.com.au
Mon-Fri / 8:30am-5pm

Dario Caravans & Repairs 

1 Pinn St
St Marys SA 5042 

08 8277 4388

RVStore Plus - A1 Caravans 

1 Kettering Rd
Elizabeth South SA 5112 

08 8287 0788