Hello, Both the HAC and the Birkin come in different sizes... lets just zoom in on the handbag sizes their are also travel versions of each
Birkin 30,35cm
HAC 32,36cm
The Birkin will have longer handles than the HAC,
Birkin 35cm verses HAC 32cm> The HAC 32 in TOGO will be less floppy than a Birkin 35cm, The HAC 32cm will be 6 inches deep verses the 35cm Birkin at 7 inches deep, The HAC 32 will appear Taller than the Birkin 35cm. Also the Hardware on these styles is different the HAC has square turnlock JPG hardware and the Birkin has a round turn lock closure. Their are pluses for each bag... The HAC 36cm is Taller than the Birkin 35cm the handles are slightly shorter and the bag is deeper by .5 inches. I hope this helps :o)