It sounds like you’re describing a Vintage Perrine 91 Aluminum Fly Box with a plastic inner “separating” lid that holds 90+ flies. Here’s what I can gather:

Features of the Perrine 91 Fly Box:
1. Material: Made of aluminum (durable and lightweight).
2. Design:
– Plastic inner separating lid – Likely a compartmentalized or adjustable divider system to organize flies.
– Holds 90+ flies – Ample storage for a variety of fly patterns.
3. Vintage Appeal: Older Perrine fly boxes are collectible among fly fishing enthusiasts.

Possible Uses & Value:
– Fly Storage: Great for dry flies, nymphs, or small streamers.
– Collectibility: Vintage Perrine boxes can be sought after by collectors.
– Durability: Aluminum construction makes it resistant to crushing.

If You’re Looking to Buy/Sell:
– Check eBay, Etsy, or vintage fishing gear forums for similar listings.
– Condition matters: Rust, dents, or broken dividers affect value.
– Original branding (Perrine logo, model 91) increases collectibility.

Vintage Perrine #91 aluminum  FLY BOX plastic inner "separating" lid 90+ FLIES!

Would you like help finding similar listings or determining its value?