Not sure how sampling was done in China.

来源: 于 2020-02-09 12:20:19 [旧帖] [给我悄悄话] 本文已被阅读：次

watch the demo video here. Swab doesn't made from cotton material. Should be nylon or polyester

https://www.youtube.com/watch?v=DVJNWefmHjE