Product Description

STH Cassettes | Replacement Polycarbonate Fly Reel Spools

Part Name: STH Cassettes (Available in Sizes 1.5, 2, & 4) Part Type: Spare/Replacement Fly Reel Spool System Material: High-Impact Polycarbonate / Synthetic Composite

Product Overview

Upgrade or restore your fly fishing reel with genuine-style STH Cassettes. Designed to offer the ultimate in on-the-water versatility, these polycarbonate replacement spools allow anglers to carry multiple fly lines—floating, intermediate, and sinking—without the weight or cost of traditional aluminum spools.

The STH cassette system revolutionized fly reel design by utilizing a lightweight, synthetic spool that "pops" into a permanent reel chassis. Whether you are replacing a cracked spool or building a library of lines for different fishing conditions, these cassettes provide the durability and precision fit required for the STH cassette reel family.

Key Features & Benefits

• Rapid Interchange System: Switch lines in seconds using the friction-fit or locking engagement specific to STH chassis designs.

• Impact Resistant: Molded from durable polycarbonate to resist cracking under the pressure of backing and fly line compression.

• Corrosion Proof: 100% synthetic construction makes these spools immune to saltwater rust and pitting.

• Cost-Effective Versatility: An economical solution for traveling anglers needing to cover various water columns without carrying extra reels.

• Translucent Body: Allows for quick identification of backing amount and line type at a glance.

Model Compatibility

STH Cassettes are size-specific. The cassette system was generally produced in three primary frame sizes (1, 2, and 3). You must match the cassette size to your specific reel frame.

Fits the following Reel Families:

• STH Reels:

  • IM Cassette Series (Sizes 1.5, 2, & 4)

  • POP Cassette Series

  • DDR Cassette

  • MR Cassette

  • ECO Cassette

• Cortland Reels:

  • Cortland Endurance Cassette

  • Cortland Turbine

  • Cortland CRI (Check specific size mapping)

• Scientific Anglers / Lefty Kreh:

  • Select System 2 Cassette models manufactured by STH (verify "Made in Argentina" markings).

Technical Specifications & Part Numbers

• Manufacturer: STH (and associated OEM brands)

• Material: Molded Polycarbonate

• Available Sizes: Size 1.5 (Small), Size 2 (Medium), Size 4 (Large)

Alternate Part Numbers (Size Dependent):

• Size 1.5: STH-CAS-01 / IM-CAS-1

• Size 2: STH-CAS-02 / IM-CAS-2

• Size 4: STH-CAS-04 / IM-CAS-4

Technician's Note: Sizing is critical. A Size 2 cassette will not fit a Size 3 frame. Most STH reels have the size number stamped on the reel foot or the back of the drag knob. For exploded views and to identify your specific frame size, please consult the schematics at www.reelschematic.com.