This is a stiff interlining placed under the collar of a juban (undershirt) when tailoring. If used as a three-piece collar core, you can get six pieces from one. By inserting the interlining under the collar, the fabric around the collar becomes less likely to show through. The top seal is not closed to prevent moisture. Please understand. Quantity: 1 piece x 10 bags Size: Approximately 118 x 11cm Material: 100% cotton Color: White Made in Japan #monn wasai tools