I am kind of new, but maybe I can help. It looks like you have a KR-808 or similar model. Look at the battery charger and you can cross reference the model # you have at this site. vapeatron.com/e-cigarette-models
If you have a KR-808;
To refill your cartridges, take the white tip with the single hole out. It pulls out kind of hard but trust me it will come out. (I have a thin needle with a hook on the end that works perfect for this) pull out the clear soft o ring. and put 1 -2 drops on the white filter in the cartridge. Replace the o-ring and white tip, wait about 5 min and you should be good to go. Do not overfill.
I am
vaping my first refill as I am typing this.
I think you can use any
e-liquid. I am using a high 16mg cart. but refilling with an 11mg liquid just to be on the safe side.
GOOD LUCK