3kg of domestic Japanese oak. Please try authentic domestic charcoal for your irori (sunken hearth), hibachi (brazier), or as supplemental charcoal for the tea ceremony. The pieces are large, and may include some with peeled bark or cracks. It holds heat well. Please use the "3N" rule (no returns, no refunds, no exchanges). Due to the charcoal shortage and unstable supply, this is a very good deal. For Okinawa Prefecture, shipping will be an additional ¥3000, so please inquire before purchasing!