Pieces Transparent Color Correction Lighting Gel Filter - Red Gel Light Filter Plastic Sheet, 8.5 x 11-Inches - Newegg.com
B+W #590/090 Red Light MRC Basic Filter (105mm) 66-1102690 B&H
Red Filter AF-24 for Prime & Partner Flashlights | Armytek.com
Subtractive Color Mixing – L.R. Ingersoll Physics Museum – UW–Madison
Amazon.com : Selens 15.8X19.7inch/40X50cm Gels Color Filter Paper Correction Gel Lighting Filter for Photo Studio Light Red Head Light Strobe Flashlight Dark Red : Electronics
Slip-on Flashlight Bezel Filters 1.25 inch | Red And Blue Filters | SureFire
Light Red Filter - Light Red Filter - 60mm Light Red Camera Lens Filter (25) (Special Order) - Heliopan US
Colour filters
67mm Circular Polarizer Camera Red Filter Color Light Remedy Underwater Diving Lens Conversion With Thread Mount - Camera Filters - AliExpress
Rosco 27 Medium Red Gel Filter Sheet 20"x24" Party Lighting - Rosco Roscolux Theatrical Colors / Party Colors Sheets
LEE Filters 150 x 150mm #23A Light Red Filter SW15023A B&H Photo
Red and green filters, illustration - Stock Image - C050/8752 - Science Photo Library
6pcs 25 * 20cm Transparent Lighting Color Correction Filters Set for Flash Light (Red/ Blue/ Green/ Cyan/ Yellow/ Magenta)|filter mann|filter magnetlight up engagement ring - AliExpress
Astro-Tech #23A Light red 1.25" color filter | Astronomics.com