CL (thread) : This thread is made from the base (synthetic thread), on which the flat copper wire is winded up.

CL(线路)：该线路是由底部穿入(合成线)，线上缠绕着扁平的铜线。

youdao

Synthetic filament yarn (other than sewing thread), not put up for retail sale, including synthetic monofilament of less than 67 deci- tex.

合成纤维长丝纱线（缝纫线除外），非供零售用，包括细度在67分特以下的合成纤维单丝。

youdao

It works like this: thread by thread technicians apply the synthetic, polyester-based extensions to each tiny lash (up to 120 an eye) leaving clients the look of full eye-make up.

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