Seaguar Basix Fluorocarbon
Diameter chart, reel capacity & backing guide
BasiX is Seaguar's value-positioned 100% fluorocarbon main line. The US range covered here uses 200-yard spools through 15 lb and a 175-yard spool at 20 lb. Compare the selected diameter with your reel to plan a full fill or a fresh working section over backing.
- Construction
- 100% fluorocarbon mainline; made in Japan
- Listed strengths
- 4-20 lb
- Line type
- Fluorocarbon main line
Is Basix right for your setup?
BasiX is a straightforward fluorocarbon main-line option when regular respooling and package cost matter. Choose a manageable diameter for the reel, particularly for a small spinning setup. A full fill keeps the line continuous; a shorter fresh section over sound backing uses less fluorocarbon while retaining the working length you need.
How much Basix will fit?
Calculated estimates, not measured fills. Stop at the reel manufacturer's fill level even if some line remains.
Seaguar Basix diameter chart
US assigned product code evidence only. Published inch/mm pairs preserved; 6lb held for unit conflict. Exact package amounts are strength-specific.
| Strength | Inches | mm | Spools (yd) |
|---|---|---|---|
| 0.007 | 0.185 | 200 | |
| 0.010 | 0.260 | 200 | |
| 0.011 | 0.285 | 200 | |
| 0.012 | 0.310 | 200 | |
| 0.013 | 0.330 | 200 | |
| 0.016 | 0.405 | 175 |
Choosing your Basix strength
The 10 lb BasiX entry is .011 inch / .285 mm, while 15 lb is .013 inch / .330 mm. The higher strength changes the fill calculation; it is not just a stronger label on the same line size.
The 20 lb entry is .016 inch / .405 mm and the assigned retail package is shorter at 175 yards. Both diameter and supplied amount change when moving up from 15 lb.
The 6 lb product code is documented but withheld from this chart because its published .008 inch and .220 mm pair exceeds normal display-rounding tolerance.
Specification-based guidance, not a hands-on Basix test. Capacity results are estimates, not measured fills.
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
Buy the assigned package
The verified packages are 200 yards for 4, 8, 10, 12, and 15 lb, and 175 yards for 20 lb. Other strength-and-length combinations are not included in this guide.
Set the working length first
A partial fluorocarbon fill over backing can conserve supply, but leave enough working line for casts, runs, and repeated reties. Stop at the reel's recommended fill level.
Distinguish mainline from a leader
BasiX can be cut for terminal use, but a short piece on braid is not the reel's working fill. Calculate the actual braid when that is what occupies the spool.
How Much Fits on These Reels?
Estimated full-spool capacity for the Basix strength selected above, with no backing. These are calculated examples, not physical tests or recommendations for every pairing.
Loading capacity estimates...
Basix questions, answered
Is BasiX fluorocarbon-coated nylon?
No. Seaguar identifies it as 100% fluorocarbon.
Is every strength sold in both 175 and 200 yards?
For the strengths included in this guide, verified packages are 200 yards through 15 lb and 175 yards at 20 lb. Other strength-and-length combinations have not been verified here.
Why is 6 lb missing from this chart?
It is a source-unit conflict, not a finding that 6 lb has been discontinued. The official .008 inch/.220 mm pair needs clarification.
Specifications & sources
Checked 2026-09-13 against Seaguar's product page and listed package options. Only verified strength-and-length combinations are included. The six-pound diameter discrepancy remains unresolved; no converted value replaces either published figure.
Calculations use the catalog's listed inch diameters. Published inch and millimeter values may differ slightly because of rounding.
- Seaguar official product evidence 1 Exact model identity and manufacturer specifications; reviewed 2026-09-13.
- Seaguar official product evidence 2 Supporting specification, package or chart evidence; see source note for scope.