Diameter chart, reel capacity & backing guide
BasiX is Seaguar's value-positioned 100% fluorocarbon mainline. The current US assigned SKUs use 200-yard spools through 15 lb and a 175-yard spool at 20 lb. The option menu alone is not the package catalog: combinations without a real SKU are excluded from this guide.
Consider BasiX for a fluorocarbon working fill when package amount and diameter fit your reel. Price positioning does not establish the same handling as another Seaguar line. Compare the actual diameter, particularly before putting a heavier strength on a small spinning spool.
US assigned SKU evidence only. Published inch/mm pairs preserved; 6lb held for unit conflict. Exact package amounts are strength-specific.
| Strength | Inches | mm | Spools (yd) |
|---|---|---|---|
| 4 lb | 0.007 | 0.185 | 200 |
| 8 lb | 0.010 | 0.260 | 200 |
| 10 lb | 0.011 | 0.285 | 200 |
| 12 lb | 0.012 | 0.310 | 200 |
| 15 lb | 0.013 | 0.330 | 200 |
| 20 lb | 0.016 | 0.405 | 175 |
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 SKU 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.
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.
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.
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.
No. Seaguar identifies it as 100% fluorocarbon.
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.
It is a source-unit conflict, not a finding that 6 lb has been discontinued. The official .008 inch/.220 mm pair needs clarification.
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.
Diameter chart, reel capacity & backing guide
BasiX is Seaguar's value-positioned 100% fluorocarbon mainline. The current US assigned SKUs use 200-yard spools through 15 lb and a 175-yard spool at 20 lb. The option menu alone is not the package catalog: combinations without a real SKU are excluded from this guide.
Consider BasiX for a fluorocarbon working fill when package amount and diameter fit your reel. Price positioning does not establish the same handling as another Seaguar line. Compare the actual diameter, particularly before putting a heavier strength on a small spinning spool.
US assigned SKU evidence only. Published inch/mm pairs preserved; 6lb held for unit conflict. Exact package amounts are strength-specific.
| Strength | Inches | mm | Spools (yd) |
|---|---|---|---|
| 4 lb | 0.007 | 0.185 | 200 |
| 8 lb | 0.010 | 0.260 | 200 |
| 10 lb | 0.011 | 0.285 | 200 |
| 12 lb | 0.012 | 0.310 | 200 |
| 15 lb | 0.013 | 0.330 | 200 |
| 20 lb | 0.016 | 0.405 | 175 |
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 SKU 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.
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.
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.
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.
No. Seaguar identifies it as 100% fluorocarbon.
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.
It is a source-unit conflict, not a finding that 6 lb has been discontinued. The official .008 inch/.220 mm pair needs clarification.
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.
