It looks like you’re referring to a vintage NOS (New Old Stock) Scientific Anglers Inc. floating fly line, specifically the L-6-F Green, 25-yard model. Here’s some helpful information about this item:

Key Details:
– Brand: Scientific Anglers (a well-respected name in fly fishing, now owned by Orvis).
– Model: L-6-F (likely indicating line weight 6, floating F).

Vintage NOS Scientific Anglers Inc - Floating Fly Line - L-6-F Green 25 Yards

– Color: Green.
– Length: 25 yards (shorter than modern fly lines, which are typically 90 feet/30 yards).
– Condition: NOS (New Old Stock) means it’s unused but may be decades old.

Vintage Significance:
– Scientific Anglers was a pioneer in synthetic fly lines (post-silk era).
– Early plastic-coated lines (like this one) were innovations in the mid-20th century.
– The 25-yard length suggests it may date back to the 1960s–1980s, as modern lines are longer.

Collectibility & Use:
– Collectors: Vintage fly fishing gear has a niche market, especially unused NOS items.
– Usability: If stored properly, it might still be fishable, but plastic coatings can degrade over time (check for stiffness or cracking).
– Compatibility: Designed for older reels with smaller arbors; may not perform well on modern large-arbor reels.

Potential Value:
– If sealed/unused, it could appeal to collectors ($20–$50+ depending on demand).
– For practical use, modern floating lines (like SA’s current Mastery Series) outperform vintage ones.

Would you like help identifying a specific era or tips on testing its condition?