I buy this kind of seal oil every year for my parents and my grandparents in China. This is the only seal oil I ever seen in stores (GNC). (Sorry...cannot type English now...)
This type of seal oil is more expensive than the others...not exactly sure why...but since it works really well on my parents and and my grandparents (for diabetes and hypertension)...I keep buying this...
Found a store that can give me really good wholesale price. $18.00 (tax included).