These are Veniard's Goose Biots that come with approximately 4 strips in a pack.
This is great value for money for those not wishing to buy too many biot feathers.
The biots come in individual dyed colours, mixed assorted colours or mixed fluorescent colours.
Goose biots are durable, stiff barbs found along the back of the primary flight feather from a goose.
The biots are most commonly used for different colours when Trout fly tying or Nymphs.
These biots work well as leg patterns and split tail patterns on Nymph flies.
Additionally, they can be used on Buzzers as cheek patterns.
Goose Biots can come in different length sizes so although it's not normally done, you can use the longer ones for wrapping body patterns.
It's also ideal to use the shorter ones for when you are tying tails and legs.
Common flies that use the Goose Biots is the very famous Prince Nymph, GRHE Prince Nymph and the Copper John.