Oak Chips for 25 liter Wine or Liquor.
For wine, brandy whiskey or other types of spirits. One bag is sufficient for 25 liter wine.
You don't need oak barrels for getting the oak taste, chips and oak rods are used in commercially produced wine and in liquor, usually in combination with barrels to get the real authentic story... Since the surface area is much larger on chips compared to barrels the taste of oak extracts fast.
Add this already in the beginning of the fermentation if you make wine. Provides a strong character of oak aging of the wine. For liquor it is harder to give a general recommendation, try it out with 5-10 liters and let it age, taste once a day to begin with or once a week after a while to see when you are happy with the result.