The side that you want to be able to see through to needs to be at least 4:1 brighter than the room you don't want people to be able to see into. All reflective films work in this way there is no film that does not work in this way.
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20PCS Halloween Black Velvet Fabric Sticky Back Adhesive Back Sheets, A4 Sheet (8.3" x 11.8"), Self-Adhesive Durable Water
Aliexpress UK
1.5 mtr This is like a one way glass type of film which is almost like your CID room window effect! You can see out but the view inwards is restricted to a limit but not totaly blocked! Great for privacy!
eBay
Hang Tabs, 200 Pcs Clear Sticky Hanging Tabs Slot Hole Self Adhesive Plastic Hang Tags, 4.5 X 3.5cm
Aliexpress UK
STICKY BACK PLASTIC SELF ADHESIVE VINYL FILM. WOODGRAIN VINYL. MARBLE VINYL. WINDOW VINYL. VINYL TILES. Woodgrain Vinyl. Marble Vinyl. Window Vinyl.
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SUNFLO Hang Tabs, 600 Pcs Clear Sticky Hanging Tabs Slot Hole Self Adhesive Plastic Hang Tags, 4.5 X 3.5Cm
Aliexpress UK
MIRROR STICKY BACK PLASTIC SELF ADHESIVE VINYL FILM. BUY AS MANY AS YOU LIKE JUST PUT THE QTY IN THE BOX AT THE TOP OF THE PAGE. WoodGrain Vinyl. Marble Vinyl. Window Vinyl. 67.5Cm Wide. Woodgrain Vinyl.
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A4 115gsm Self-Adhesive Photo Paper, 50 Sheets, Glossy Sticky Back Printing Paper for Inkjet Printers, Peel and Stick Photos,
Aliexpress UK
The vinyl can be difficult to manoeuvre on surfaces like glass and appliances, lightly spray water first. Unlike solvent based adhesives, dcfix has a water based low tack adhesive that allows you to reposition the vinyl during application, it then bonds fully within 24 hours, remove using heat from a hairdryer.
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1Pcs/45sheet Early Foam Back Card Series National Style Flower Sticky Notes Stationery N Times Sticker Kawaii Stationery
Aliexpress UK
STICKY BACK PLASTIC SELF ADHESIVE VINYL FILM. IF YOU REQUIRE A LONGER LENGTH WITHOURT A JOINT JUST PUT THE QTY IN THE BOX AT THE TOP OF THE PAGE. SIMPLY PEEL AND STICK. WOODGRAIN VINYL. MARBLE VINYL.
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6/12/20pcs Islamic Eid Mubarak Money Cards Compatible for Ramadan - Plastic/Paper Wallets with EID Backs Greetings, for - Muslim
Aliexpress UK
1.5 mtr This is like a one way glass type of film which is almost like your CID room window effect! You can see out but the view inwards is restricted to a limit but not totaly blocked! Great for privacy!
eBay
50 Sheets A4 Holographic Sand Foil Adhesive Tape Back Broken Glass Heart Cold Laminating Film On Paper Plastic DIY Package Card
Aliexpress UK
STICKY BACK PLASTIC SELF ADHESIVE VINYL FILM. IF YOU REQUIRE A LONGER LENGTH WITHOURT A JOINT JUST PUT THE QTY IN THE BOX AT THE TOP OF THE PAGE. SIMPLY PEEL AND STICK. WOODGRAIN VINYL. MARBLE VINYL.
eBay