2.2 Sale by sample Sale by seller's sample ◆ Sale by buyer' s sample★★ ◆(1) Counter sample 2)Sealed sample ()Safeguard clauses. 4)Reference sample2.2 Sale by sample  Sale by seller’s sample  Sale by buyer’s sample  (1) Counter sample:  (2)Sealed sample:  (3)Safeguard clauses:  (4)Reference sample: ★★