Stren Fluorocast
Diameter chart, reel capacity & backing guide
This guide covers Stren FluoroCast Clear from the 2014 US catalog: 4-17 lb on 100- and 200-yard spools. It is listed separately from Stren 100% Fluoro, which has its own diameters. These are older specifications, so check the label and condition of the line you own.
- Construction
- 100% fluorocarbon mainline
- Listed strengths
- 4-17 lb
- Line type
- Fluorocarbon main line
Choose the full mainline plan before the package
FluoroCast was positioned as a castable fluorocarbon mainline. Use the exact 2014 diameter to decide how much fits, then choose between a full fresh fill and a shorter working section over backing. A 100-yard pony spool can be useful for a limited working section, but package size alone says nothing about whether the remaining cast and fighting reserve is adequate.
How much Fluorocast will fit?
Calculated estimates, not measured fills. Stop at the reel manufacturer's fill level even if some line remains.
Stren Fluorocast diameter chart
2014 US FluoroCast Clear only, LEFT table on catalog page 6: 4/6/8/10/12/15/17 lb, 100-yard pony and 200-yard filler. The separate 100% Fluoro table at right does not supply any values. No 20 lb FluoroCast row is inferred.
| Strength | Inches | mm | Spools (yd) |
|---|---|---|---|
| 0.007 | 0.1778 | 100, 200 | |
| 0.009 | 0.2286 | 100, 200 | |
| 0.010 | 0.254 | 100, 200 | |
| 0.012 | 0.3048 | 100, 200 | |
| 0.013 | 0.3302 | 100, 200 | |
| 0.015 | 0.381 | 100, 200 | |
| 0.016 | 0.4064 | 100, 200 |
Choosing your Fluorocast strength
The 4-8 lb entries are the light end of this edition. Use them only where tackle and conditions suit the strength; extra capacity cannot compensate for an undersized line.
The 10 and 12 lb entries are .012 and .013 inch respectively in the FluoroCast table. Do not borrow the neighboring 100% Fluoro chart, whose strength-to-diameter mapping differs.
The upper verified steps are 15 and 17 lb, at .015 and .016 inch. A 20 lb FluoroCast row is not in this source and remains excluded.
No independent casting, knot, shock or underwater visibility test was performed. Manufacturer handling and visibility statements are positioning, not a ReelCalc guarantee.
Want a guided recommendation?
Continue in the Setup WizardSame pound test, different diameters
At your selected strength
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What changes with another line?
Nearby diameters in the line database
| Line | Strength | Inches | Difference |
|---|---|---|---|
| Loading line database... | |||
Backing, working line & leaders
Read FluoroCast on the package
Look for the gray-and-black FluoroCast family, not the blue 100% Fluoro package. Both contain fluorocarbon, but shared material is not proof of the same diameter or specification.
Compare 100 and 200 yards
The 2014 chart assigns both pony and filler formats to every listed 4-17 lb strength. Use the 200-yard option for a larger fresh fill or check a 100-yard working section against the required reserve.
Keep backing below the working line
If you retain backing, leave the connection below the longest expected cast and extra line needed during a fight. Use the calculator's exact diameter input for both sections.
Inspect before loading
Check the package identity, line condition and a carefully seated knot. Wind evenly and follow the reel's specified fill clearance; historical packaging does not establish the condition of an old spool.
How Much Fits on These Reels?
Estimated full-spool capacity for the Fluorocast strength selected above, with no backing. These are calculated examples, not physical tests or recommendations for every pairing.
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Fluorocast questions, answered
Is FluoroCast the same as Stren 100% Fluoro?
No equivalence is established. The 2014 catalog presents them as separate named families with separate diameter tables and colors. This guide uses FluoroCast Clear only.
Why is 20 lb excluded?
FluoroCast's 2014 table ends at 17 lb. The 20 lb row belongs to the neighboring 100% Fluoro family and cannot be transferred.
Are 100-yard packages leader spools?
The source calls them pony spools for the FluoroCast mainline family. A shorter package can support a working section, but this chart does not recategorize the product as leader-only.
Do both lengths apply to each listed strength?
Yes. The 2014 Clear table explicitly covers 4-17 lb for both 100-yard pony and 200-yard filler formats. That is a historical specification, not a current stock statement.
Are the millimeter values also printed?
No. The chart prints inches. Millimeters here are calculated as inches multiplied by 25.4, without importing a different regional table.
Specifications & sources
Checked September 13, 2026 against the original 2014 Stren catalog preserved by WesternBass. All inch values, Clear availability dots and both package legends were visually reviewed. Millimeters are explicit conversions. Image p6_i78 is original FluoroCast artwork from that edition, not neighboring 100% Fluoro. No retailer numbers are used.
Calculations use the catalog's listed inch diameters. Published inch and millimeter values may differ slightly because of rounding.
- 2014 manufacturer FluoroCast chart Sole numeric authority; left-hand table, Clear column and both package legends visually checked.
- 2014 catalog edition manifest Identifies the dated publication and original page assets.
- Original FluoroCast artwork Unmodified 2014 gray-and-black FluoroCast package, distinct from 100% Fluoro.