Fly Tying Materials

Flash Materials for Fly Tying

October 20, 2025

In fly dressing, flash material is used to add shine, shimmer, and sparkle to a fly to make it more attractive to predatory fish. It mimics the glint of scales or the distress signal of a struggling baitfish, and it can be incorporated into various parts of the fly, such as the tail, body, or wings. Flash can be made from synthetic, glossy fibers and is used to enhance the visibility and allure of streamers, nymphs, and wet flies.

Pearl flash has an iridescent, mother-of-pearl sheen, while holographic flash displays a rainbow of colors that shift with the light. UV flash is treated to reflect ultraviolet light, making it more visible to fish in deeper or murky water, and grizzly flash is a synthetic material with a barred, colored appearance, not a type of shimmer. Each flash type serves to attract fish with different visual effects: pearl and holographic create a general sparkle, while UV adds specific visibility, and grizzly mimics a barred pattern on baitfish.

Differences between fly tying flashes

Flash Type	Description	Applications
Pearl	Has a smooth, iridescent, mother-of-pearl shine, similar to the inside of a shell.	Great for creating a subtle, bright flash in a variety of flies, including nymphs, streamers, and dry flies.
Holographic	Displays a full spectrum of colors that change as the light hits it, giving it a “sparkling” or “rainbow” effect.	Adds a strong, eye-catching sparkle and can mimic the scales of baitfish. It is effective for both small and large flies.
UV	Treated to reflect ultraviolet (UV) light, which is invisible to the human eye but visible to many fish.	Excellent for deep-water flies, as it increases visibility in low-light conditions or murky water. Also used in flies for clear water where a specific, fish-attracting color is needed.
Grizzly	A synthetic material that features a barred pattern, similar to the natural feather of a grizzly hen.	Primarily used for its appearance, mimicking the natural, barred patterns of baitfish. Can be used for wings, tails, and bodies on various flies, especially nymphs and streamers.

Key differences in function and application

Subtle vs. bright: Pearl offers a more subtle, realistic shimmer, while holographic provides a more pronounced, flashy, multi-colored effect.
Specific wavelength: UV flash is designed to reflect a specific wavelength of light (UV) that fish can see, making it a specialized tool for certain conditions.
Pattern mimicry: Grizzly flash is unique in that its primary purpose is to mimic a specific natural pattern (a barred appearance), whereas the other flashes primarily focus on general reflectivity and shimmer.
Depth: UV is most beneficial in deep water or low light, while pearl and holographic can be used effectively at any depth, with holographic providing more movement and attention.