Diameter chart, reel capacity & backing guide
Mastiff FC is Shimano's NANOARMOR fluorocarbon. This guide covers MASTIFF FC 90m with exact numeric SKU and japanAdminCode values, as documented on Shimano's Brazilian product page. It does not silently combine that package with US 200-yard stock.
Consider this version when you are buying a 90-meter Mastiff FC package for a fluorocarbon working fill. Shimano describes the surface structure as a knot-retention feature; it is not a guarantee against knot failure. A short imported spool needs a deliberate reserve and backing plan.
Shimano pt-BR MASTIFF FC 90m. Exact numeric SKU/japanAdminCode values from the product table. Inch diameter and yard length converted from metric data.
| Strength | Inches | mm | Spools (m / yd) |
|---|---|---|---|
| 4 lb | 0.006496 | 0.165 | 90 m (about 98.43 yd) |
| 5 lb | 0.007283 | 0.185 | 90 m (about 98.43 yd) |
| 6 lb | 0.008071 | 0.205 | 90 m (about 98.43 yd) |
| 8 lb | 0.009252 | 0.235 | 90 m (about 98.43 yd) |
| 10 lb | 0.010236 | 0.260 | 90 m (about 98.43 yd) |
| 12 lb | 0.01122 | 0.285 | 90 m (about 98.43 yd) |
| 14 lb | 0.012205 | 0.310 | 90 m (about 98.43 yd) |
| 16 lb | 0.012992 | 0.330 | 90 m (about 98.43 yd) |
| 18 lb | 0.01378 | 0.350 | 90 m (about 98.43 yd) |
| 20 lb | 0.014567 | 0.370 | 90 m (about 98.43 yd) |
The exact 5 lb diameter is .185 mm, and 6 lb is .205 mm. Those product-specific numbers should not be replaced with retailer values rounded to two decimal places.
The 10 lb entry is .260 mm and 16 lb is .330 mm. Choose the appropriate tackle first, then recalculate capacity as diameter increases.
The 6 lb strength is verified under numeric SKU/japanAdminCode 868572 even though it was absent from the starting catalog inventory. It gets its own strength ID, not the existing 5 lb ID.
Specification-based guidance, not a hands-on Mastiff FC test. Capacity results are estimates, not measured fills.
A 90-meter package contains about 98.43 yards. This page does not present a US 200-yard package as an interchangeable size for the same regional SKU.
With less than 100 yards in the retail package, assess casting distance, runs, and future trimming before winding the entire package over backing.
The product is fluorocarbon despite the site's broad URL category. Match the package identity and order code, not a category name or similar family label.
No. The verified source here is the Shimano pt-BR MASTIFF FC 90m table. US 200-yard stock requires its own exact SKU evidence.
Are these inch values official?The manufacturer table supplies millimeters. Inch values are calculated conversions, clearly marked as such.
Does NANOARMOR make any knot reliable?No. It is Shimano's surface-structure technology, not a replacement for a suitable knot, careful tying, inspection, and an appropriate drag setting.
Checked 2026-09-13. Official product table verifies ten 4-20lb strengths. This config deliberately excludes unverified US 200yd package claims and does not convert kilogram average strength into new pound labels.
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
Mastiff FC is Shimano's NANOARMOR fluorocarbon. This guide covers MASTIFF FC 90m with exact numeric SKU and japanAdminCode values, as documented on Shimano's Brazilian product page. It does not silently combine that package with US 200-yard stock.
Consider this version when you are buying a 90-meter Mastiff FC package for a fluorocarbon working fill. Shimano describes the surface structure as a knot-retention feature; it is not a guarantee against knot failure. A short imported spool needs a deliberate reserve and backing plan.
Shimano pt-BR MASTIFF FC 90m. Exact numeric SKU/japanAdminCode values from the product table. Inch diameter and yard length converted from metric data.
| Strength | Inches | mm | Spools (m / yd) |
|---|---|---|---|
| 4 lb | 0.006496 | 0.165 | 90 m (about 98.43 yd) |
| 5 lb | 0.007283 | 0.185 | 90 m (about 98.43 yd) |
| 6 lb | 0.008071 | 0.205 | 90 m (about 98.43 yd) |
| 8 lb | 0.009252 | 0.235 | 90 m (about 98.43 yd) |
| 10 lb | 0.010236 | 0.260 | 90 m (about 98.43 yd) |
| 12 lb | 0.01122 | 0.285 | 90 m (about 98.43 yd) |
| 14 lb | 0.012205 | 0.310 | 90 m (about 98.43 yd) |
| 16 lb | 0.012992 | 0.330 | 90 m (about 98.43 yd) |
| 18 lb | 0.01378 | 0.350 | 90 m (about 98.43 yd) |
| 20 lb | 0.014567 | 0.370 | 90 m (about 98.43 yd) |
The exact 5 lb diameter is .185 mm, and 6 lb is .205 mm. Those product-specific numbers should not be replaced with retailer values rounded to two decimal places.
The 10 lb entry is .260 mm and 16 lb is .330 mm. Choose the appropriate tackle first, then recalculate capacity as diameter increases.
The 6 lb strength is verified under numeric SKU/japanAdminCode 868572 even though it was absent from the starting catalog inventory. It gets its own strength ID, not the existing 5 lb ID.
Specification-based guidance, not a hands-on Mastiff FC test. Capacity results are estimates, not measured fills.
A 90-meter package contains about 98.43 yards. This page does not present a US 200-yard package as an interchangeable size for the same regional SKU.
With less than 100 yards in the retail package, assess casting distance, runs, and future trimming before winding the entire package over backing.
The product is fluorocarbon despite the site's broad URL category. Match the package identity and order code, not a category name or similar family label.
No. The verified source here is the Shimano pt-BR MASTIFF FC 90m table. US 200-yard stock requires its own exact SKU evidence.
Are these inch values official?The manufacturer table supplies millimeters. Inch values are calculated conversions, clearly marked as such.
Does NANOARMOR make any knot reliable?No. It is Shimano's surface-structure technology, not a replacement for a suitable knot, careful tying, inspection, and an appropriate drag setting.
Checked 2026-09-13. Official product table verifies ten 4-20lb strengths. This config deliberately excludes unverified US 200yd package claims and does not convert kilogram average strength into new pound labels.
Calculations use the catalog's listed inch diameters. Published inch and millimeter values may differ slightly because of rounding.
