Rapala RSB4 Fillet Knife Review
Our verdict
The Rapala RSB4 is a $13.25 fillet knife with a compact 4 inch stainless steel blade and an included sheath. It carries a 4.6-star rating across 264 reviews, and the 300+ units bought last month is the highest demand figure of any fillet knife in this comparison, signaling strong recent popularity at a low price.
Check price on AmazonBest for
Anglers who need a small, precise blade for trimming fish rather than breaking down larger catches, and who value the 300+ bought last month as a sign of strong current demand at $13.25.
Skip if
Skip it if a 4 inch blade is too short for the fish you handle. The Rapala BPFNF7SH1 offers a longer 7.5 inch blade, and the Kershaw 1259X extends to 9 inches for bigger cuts.
- Material Stainless Steel
- Length 4 Inches
- Size 4"
- Color Multi
- Pieces 1.0 Count
- Feature Sheath
- Priced 59% below the category median ($32.23 across 74 tracked models)
Our scorecard
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Owner rating4.6/5
4.6 average across 264 owner ratings
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Popularity2.2/5
264 owner reviews, fewer than most models here
The overall score is owner satisfaction weighted by how many reviews back it, so a high rating from few reviews counts for less. The bars below show where this model stands against the other fishing gear and tackle we track in this category on price, popularity and size. Context, not marks against it, and our read of the data, not a lab test.
Overview
A short, precise blade is what most anglers reach for when trimming smaller fish or cleaning up a fillet rather than breaking down a large catch, and the Rapala RSB4 is built for exactly that job. At $13.25, it pairs a 4 inch stainless steel blade with a sheath, making it the shortest and one of the cheapest fillet knives in this comparison.
The 4 inch length is noticeably shorter than the 7.5 inch blades on the Rapala BPFNF7SH1 and PGEF1 or the 9 inch Kershaw 1259X, positioning the RSB4 as a detail knife rather than a do-everything blade. Stainless steel construction keeps it corrosion resistant for repeated use around water, and the included sheath covers the edge when it is packed with other gear.
What stands out most is demand: 300+ units bought last month is the highest figure among every fillet knife in this set, well ahead of the 126SP's 100+ and the Kershaw 1259X's 50+. That pairs with a 4.6-star rating across 264 reviews, matching the Kershaw 1259X's score, sitting above the BP136SH's 4.4 stars, and landing just below the 4.7-star Rapala BPFNF7SH1 and BPFNF9SH1 models, making the RSB4 a small, fast-moving, well-reviewed pickup at a low price point.
Pros
- 300+ units bought last month, the highest recent demand figure of any fillet knife in this comparison
- 4.6-star rating across 264 reviews, tying the Kershaw 1259X and beating the BP136SH's 4.4 stars
- Priced at $13.25, among the cheapest options alongside the $10.49 126SP
- Stainless steel blade construction for corrosion resistance
- Includes a sheath to protect the 4 inch edge when packed
- Listed as in stock at time of writing
Cons
- 4 inch blade is the shortest in this comparison, well below the 7.5 inch and 9 inch options
- 264 reviews is a smaller sample than the 1,100 for the PGEF1 or the 1,500 for the Kershaw 1259X
- Not suited to larger fish that need a longer blade for full fillets
- No weight is listed for this model, unlike several other knives in the comparison
Specifications
| Material | Stainless Steel |
|---|---|
| Length | 4 Inches |
| Size | 4" |
| Color | Multi |
| Pieces | 1.0 Count |
| Feature | Sheath |
Performance notes
A 4 inch stainless steel blade is built for precision trimming and cleanup work rather than breaking down large fish, which is a different job than the 7.5 inch blades on the Rapala BPFNF7SH1 and PGEF1 or the 9 inch Kershaw 1259X. Stainless steel resists corrosion from repeated exposure to water and fish, a practical need for a knife that gets used often. The included sheath protects the shorter blade during storage and transport, similar to the sheath bundled with the budget-priced 126SP. At $13.25, the RSB4 sits near the bottom of the price range in this comparison, and its 300+ bought-last-month figure suggests it is being picked up frequently as a companion blade or a lower-cost option rather than a single do-everything knife.
What buyers say
A 4.6-star rating across 264 reviews places the RSB4 in a virtual tie with the Kershaw 1259X's 4.6 stars, ahead of the BP136SH's 4.4 stars, and just short of the 4.7-star Rapala BPFNF7SH1 and BPFNF9SH1. What separates the RSB4 is demand: 300+ units bought last month is the highest of any fillet knife in this set, more than double the 126SP's already-strong 100+ and six times the Kershaw 1259X's 50+. That combination of a solid rating and clearly leading purchase volume suggests the RSB4 has found a steady audience at its $13.25 price point.
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Frequently asked questions
Is the Rapala RSB4 good for bigger fish?
Not on its own. At 4 inches, its blade is the shortest in this comparison, built for trimming and detail work rather than full fillets on larger catches. Anglers targeting bigger fish are better matched by the 7.5 inch Rapala BPFNF7SH1 or the 9 inch Kershaw 1259X.
How does the RSB4's demand compare to other fillet knives?
It leads the comparison with 300+ units bought last month, ahead of the 126SP's 100+ and the Kershaw 1259X's 50+. Combined with a 4.6-star rating across 264 reviews, that makes the RSB4 the fastest-moving fillet knife in this particular lineup.
Does the RSB4 come with a sheath?
Yes, the listing includes a sheath alongside the 4 inch stainless steel blade. That matches the accessory bundled with the budget-priced 126SP, giving buyers edge protection without paying extra for a separate case on top of the $13.25 asking price.