1. The Defendant (Counterclaim Plaintiff) paid KRW 29,600,000 to the Plaintiff (Counterclaim Defendant) and its related amount from January 1, 2017 to June 19, 2018.

1. The following facts may be found either in dispute between the parties or in each entry in Gap evidence 2 to 7, 12, and Eul evidence 1 and 2 (including branch numbers), with a comprehensive view to the whole purport of the pleadings:

On September 19, 2016, the Plaintiff entered into a contract with the Defendant to deliver heating apparatus cases of 100 (24,000,000 won per unit price of 1 unit price of KRW 24,000,000, value-added tax separate, and October 5, 2016) and burning room of 300 (24,00,000,000 won per unit price of 1 set of KRW 80,00,000, value-added tax separate, and date of payment) (hereinafter “instant supply contract”).

B. Article 1(2) of the instant supply contract provides that “The variety, quantity, and payment period of a product may be modified through mutual agreement.” Article 6 of the instant supply contract provides that “If a contract was made normally, 30% of the contract amount shall be paid in advance, and the remainder shall be paid in full as of the end of the following month after the completion of the supply.”

C. On September 27, 2016, the Plaintiff received advance payment of KRW 14,400,000 from the Defendant, and began to manufacture heating apparatus cases and burning rooms, supplied 100 heating apparatus cases between October 15, 2016 and October 27, 2016, and supplied 100 heating apparatus burning rooms on October 17, 2016.

On November 11, 2016, the Defendant sent a performance promotion note to the Plaintiff, and on November 19, 2016, the heating apparatus case 100 and the heating apparatus burning room 100 feet were supplied after the due date stipulated in the instant supply contract, and yet the burning room 200 feet was not supplied, and the remainder of the burning room demanded prompt supply. On November 19, 2016, the Plaintiff supplied 100 feet to the Defendant.

E. On November 25, 2016, the Defendant entered into a supply contract with the Plaintiff on November 25, 2016, since the Plaintiff failed to observe the payment period under the instant supply contract, but the heating engine combustion room was not supplied.