FENDER Patented Callus Builder & Finger Strengthener – Resistance Finger Exerciser for Guitar, Bass & Violin – Guitar Finger Trainer & Grip Strength Tool – Ideal Guitar & Bass Accessories (Tensions: RED=8-Lbs; BLACK=15-Lbs)
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Availability:
In Stock.
Arrives
Thursday, Jul 30
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Size: 8-Lb, 15-Lb
Color: Red, Black
Features
- ESSENTIAL GUITAR & BASS ACCESSORY From beginners to pros, this must-have guitar finger trainer improves strength, coordination, and enduranceperfect for daily guitar training or warm-ups before a performance.
- LICENSED and PATENTED FENDER CALLUS BUILDER Designed in the shape of Fenders iconic Stratocaster, this officially licensed guitar callus builder is a standout in any collection of guitar & bass accessories.
- RAISED STRING-LIKE RIDGES Unlike typical strength training grip strengtheners, this exclusive patented design includes raised ridges that simulate real string tension to help build callusesideal for realistic guitar finger exerciser practice.
- MIRRORS PLAYING POSITION Ergonomically shaped to replicate your hand and finger angles while playing any stringed instrument, making it a versatile tool to build calluses where you need them.
- HIGHEST TENSION AVAILABLE Included both 8-lb (RED) or 15-lb (BLACK) resistance. The BLACK version delivers extreme resistanceunmatched by any other guitar finger trainer or hand exerciser on the market.
- PERFECT HOLIDAY GIFT & STOCKING STUFFER A thoughtful holiday gift that shows you support their musical journey. The ideal add-on for anyone receiving a new guitar! Compact, affordable, and fun to use musicians of all ages LOVE this in their stocking.
Color: Red, Black
Material: Plastic
Brand: Fender
Item Weight: 6 ounces
Style: Guitar-shaped
Brand Name: Fender
UPC: 891922002230
Manufacturer: Barrett Productions, LLC
Item Type Name: Callus Builder
Model Number:
Part Number:
Warranty Description: NO
Color: Red, Black
Style: Guitar-shaped
Item Weight: 6 ounces
Material: Plastic
Tension Supported: Heavy
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Thursday, Jul 30
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Size: 8-Lb, 15-Lb
Color: Red, Black
I use these to keep calluses on finger tips especially when I’m at work. Thereby maintaining calluses so I can play guitar easier. I also notice more strength in fingers.
Reviewed in the United States on May 17, 2026 by BD Keen
Size: 15-Lb
Color: Black
I haven't experience any issues like some other reviews have talked about with the unit breaking after some days of using it. I've been using this mostly daily for almost a month now and it works very well. Plastic and rubber(or maybe silicone?) parts look and feel thick and sturdy. Maybe it would cause an issue if you squeeze very hard and fast over and over, but that's not how you should use this product anyway. The goal isnt to squeeze as hard as you can. I press hard but not too hard to where it's painful, slowly do a few reps squeezing the clip about halfway, causing deep imprints on my finger tips. Then i move my fingers left, right, up, down while i hold down on a single line. Which essentially just tugs the skin on your finger tips in every direction, causing your skin to want to callus even more. Honestly i think pulling the skin causes callus more than just pressure on an area. Haven't tried the magnet but it seems firmly attached by a blot of glue. The magnet does move around a tad so if you used the magnet on a daily basis i can see maybe eventually it would fall off and you would have to re-glue it. Really not a big deal. I'm honestly not sure why this isn't more of a common tool you see around. Searching Amazon this one is really the only one that pops up. Definitely works though.
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Reviewed in the United States on October 1, 2024 by Stephen McSpirit
Size: 8-Lb
Color: Red
Cool gadget! Seems working on my calluses…
Reviewed in the United States on May 25, 2026 by Artak Saroyan
Size: 8-Lb, 15-Lb
Color: Red, Black
I recently started up playing guitar again after taking a hiatus for a couple years. Unfortunately, the calluses I built up long ago faded away. I bought this set of callus builders to see if I could accelerate the process of building up callus. I debated buying only the 15 lb. device but opted to pay a little more and buy the set of both the 8 lb. and 15 lb. devices. I’m glad I did. Both weights will strengthen your fingers and help build callus, but my 70 year old fingers found the lighter one easier to use, at least until I can build up more finger strength. But both are definitely helpful, and they’re easy to use while watching TV. My only complaint is these devices are somewhat small. I have to bunch my fingers up a little bit to fit all 4 fingertips on the device to build callus. It would have been better if these were about 1/4 inch wider. Overall, I’m pleased with these callus builders. They’re kind of expensive for glorified potato chip bag clips, but they work as advertised, and I’m sure I’ll get a lot of use out of them.
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Reviewed in the United States on December 1, 2025 by Terry R. Nye
Size: 8-Lb
Color: Red
This is my 2ed one and booth springs broke in about 3 months . Im not buying another one. Will ask for new spring.
Reviewed in the United States on January 23, 2026 by Pockets
Size: 8-Lb
Color: Red
This little bugger works great for getting some callus going! When I first started playing, I couldn't press on the strings hardly at all without my fingers hurting so bad I couldn't do anything with the guitar but then started carrying this thing around working it often and had some nice hard spots on my fingers in less than 2 weeks.
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Reviewed in the United States on June 1, 2026 by Ted Graham
Size: 8-Lb
Color: Red
Works as a chip bag clip. Rough parts seem to work on the fingertips that should build callouses over time. Over time the friction seems to breakdown the plastic at the pivot point. Fits nicely in the hand as well. Could be a bit harder to squeeze for my strength though. Very simple to use. The design is very cool as well.
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Reviewed in the United States on May 6, 2026 by Matthew W. Ruhlman
Size: 8-Lb
Color: Red
Does what it's supposed to do; that is help you develop callouses, to make playing guitar easier, and more effective.
Reviewed in the United States on May 10, 2026 by flintlock