Polarized Film Sheets 3 PCS 8.2x5.9in/ 21x15cm Polarizer Linear Polarizing Filter Non-Adhesive for Educational Physics Photography Lighting. Specification: Polarization: Linear，Greater than 99.9% Size: 21x15cm Thickness:0.22mm Feature: Polarizing film have protective film on both sides, before you use it, you have to peel a protective film off the front and back.
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