Polarized Film Sheets 3 PCS 8.2x5.9in/ 21x15cm Polarizer Linear Polarizing Filter Non-Adhesive for Educational Physics Photography Lighting

This is a fun product to show kids how they should always be careful about drawing conclusions from observations, and how observations can sometimes seem to be contradictory. NOTE - the sheets have protective film on both sides which must be peeled off - I did not realise and removed it from only one side, then thought they were rather cloudy. It took me a while to notice the additional film.

I had to tape this over my led lights and experiment with rotating them, all worked fine in the end would recommend

do not recommend buying it! In addition to costing a lot, they have a very strong tendency to roll up (probably after a very long time left rolled up on themselves). I tried to flatten but the result is very bad because the film forms wrinkles due to the shape it was used to, tending to roll ... this lack of care of the product in storage makes it unusable. Also difficult to clean.