FENDER Patented Callus Builder & Finger Strengthener – 15-lb Resistance Finger Exerciser for Guitar, Bass & Violin – Guitar Finger Trainer & Grip Strength Tool – Ideal Guitar & Bass Accessories

Like most people starting out on guitar I find 15 or 20 minutes into playing I have to stop. My fingers hurt, and I lack strength and flexibility in my ring and pinky fingers in particular. I leave this in my car and I use it similarly to a stress ball. My callouses have and I find I can now practice for an hour or more. Better than that though, my playing is much better because I have the strength to properly press the strings. Now if I can figure out how to stretch out my fingers I’ll be doing great. This is a simple gator clip with 15 lbs of tension and a bumpy surface on one side, so simple but incredibly effective.

Preparing to play again, this nifty device helps me to harden up my fingertips again! This 15-pound unit requires a bit of strength, and it prompted me to order and begin with the 8-pound FENDER callus builder first!No problems with the unit so far, and I now use both daily. My fingers are stronger, callus formation happening, and the price was great with fast shipping! The magnet is great to store them on my metal cabinet door.Highly recommended for new guitar players or returning back to strings!!

So far so good. When not practicing and watching TV it’s a fun passive thing to do to build strength and callous build up. But I also need to remember to practice practice practice. Just by practicing muscles and callous will happen naturally. But maybe this little gadget is a small hack to build finger strength early and get through finger tip pain quicker. 🤘

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.

I’ve been needing something to keep my fingers strong and to maintain my callouses when I have long trips where I can’t bring my guitar. I use this all them and it’s awesome. Keeps my fingers strong and ready to play even if I can’t use my instrument. Great travel size.

Very very cheap.The magnet is so darn cheap that it cant even hold the weight of the object when it is by itself, let alone when you try to clip it to something. Also, because it is so heavy and so cheaply made (using double sided foam tape to hold the magnet on) it will eventually fail by itself and fall. Which is how I go the above picture. Which now at least makes sense, because the so called "magnet" that they used was just a steel casing and not even the real magnet. The real one is the small disc stuck to the middle disc in the photo. So, they used cheap materials to hold it in place, and a cheaper smaller magnet within a larger casing so it looks bigger than it really is. And it was engineered in such a way that it just barely manages to hold its own weight.Let that sink in for a bit. They spent the time, money, and resources to engineer it this way. The absolute cheapest way possible. This was done purposefully. I would give zero stars if I could. What a piece of junk. I wish it would have failed sooner so I could have gotten my money back. 0/5 stars.

So I bought this because my middle to pinky fingers are not building fast enough for me. I decided to order this because well its only $16.First day I had it I used it all day for hours. When the fingers and hand got really sore I put it down for a shot bit then started back again.Second day. My hand was in extreme pain. I kept trying to use it on and off all day again even using my other hand to help press down on this thing. Towards the end of the evening the three fingers I was hoping to build up was showing signs that it was working.Third day. Today the fingers really are starting to develop so I have no doubt that this thing will work. My fingers are quite sore but its bearable.Important note: People should be using this for the tips of there fingers not the pads. I am sure that the pads could also benefit especially if you have short fat fingers like mine.The more you use it the faster it will work.

Works as advertised, I purchased their other version (red) as 15 pounds was too hard for me to start with. Excellent product.