--- product_id: 24534652 title: "Brock String, Vision Convergence Insufficiency Training Tool for Eye Muscle Strengthening, Focus Exercise and Agility" brand: "brock string" price: "Β₯2844" currency: JPY in_stock: true reviews_count: 13 category: "Brock String" url: https://www.desertcart.jp/products/24534652-brock-string-vision-convergence-insufficiency-training-tool-for-eye-muscle store_origin: JP region: Japan --- # 6 ft precision training length Durable nylon & polypropylene string Strengthens eye muscles & focus Brock String, Vision Convergence Insufficiency Training Tool for Eye Muscle Strengthening, Focus Exercise and Agility **Brand:** brock string **Price:** Β₯2844 **Availability:** βœ… In Stock ## Summary > πŸ‘οΈβ€πŸ—¨οΈ See the difference, own the game. ## Quick Answers - **What is this?** Brock String, Vision Convergence Insufficiency Training Tool for Eye Muscle Strengthening, Focus Exercise and Agility by brock string - **How much does it cost?** Β₯2844 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/24534652-brock-string-vision-convergence-insufficiency-training-tool-for-eye-muscle) ## Best For - brock string enthusiasts ## Why This Product - Trusted brock string brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Sharper Vision, Sharper Edge:** Boost your eye muscle strength and convergence for unbeatable focus in sports and daily life. - β€’ **Pro-Level Visual Coordination:** Enhance hand-eye coordination and depth perception to outplay the competition. - β€’ **Effortless Setup, Instant Gains:** Simple to use with a short learning curveβ€”start training your eyes anytime, anywhere. - β€’ **Built to Last, Built for Results:** Premium durable string and high-quality beads ensure consistent performance session after session. - β€’ **Guided Training for Maximum Impact:** Includes clear instructions so you train smarter, not harder, and see real improvements fast. ## Overview The Brock String is a 6-foot durable eye training tool designed to strengthen eye muscles, improve convergence, and enhance focus. Crafted with high-quality nylon string and beads, it supports vision exercises for athletes and professionals seeking better hand-eye coordination and depth perception. Easy to set up and use, it comes with clear instructions to maximize training effectiveness at home or on the go. ## Description Take your vision and athletic performance to the next level with the Brock String, a versatile sight adjustment tool designed for hand eye coordination training, vision exercise, and depth perception training. Ideal for athletes, hobbyists, and anyone looking to improve visual skills, this tool strengthens eye muscles while enhancing focus and precision. By practicing with the Brock String, you can enhance eye tracking, alignment, and coordination, giving you a competitive edge in sports or daily activities that demand sharp vision. Setup is simple and intuitive, making this vision exercise tool suitable for both beginners and advanced users. The durable string and high-quality beads provide long-lasting performance, ensuring consistent results over repeated sessions. A clear, included instruction guide walks you through proper use and tips to maximize your training, so you can confidently practice at home or in the gym. Review: Good quality, easy to use - It's good. The beads slide easily but stay where you put them. The string is easy to tie and untie. The string can be drawn taunt and bounce is easily controlled. Review: Great for eye convergence - This string provides a means to work on convergence problems. I have excellent vision in my eyes but when I'm tired etc. I start seeing double --especially watching the television. I can see improvement after just a few sessions of the exercises. Hopefully before long I will no longer have the problem. Comes with instructions in English! They just don't indicate how long one should do them. If you get one, practice at least a few minutes at a time. ## Features - ENHANCE CONVERGENCE AND FOCUS: Use the Brock String convergence training tool to strengthen eye muscles, focus, and support visual performance for daily activities and sports - BOOST ATHLETIC PERFORMANCE: The Brock eye string allows precise eye training in sport-specific positions, giving you a competitive edge and enhanced visual coordination - EASY-TO-USE EYE EXERCISE TOOL: Simple setup and short learning curve let you practice convergence and eye focus exercises at home, making vision training convenient for beginners and advanced users - PREMIUM FOCUS STRING WITH BALLS: Crafted with durable string and high-quality beads, this eye muscle strengthening tool ensures long-lasting use and consistent performance for repeated vision exercises - FRONT SIGHT TOOL WITH INSTRUCTIONS INCLUDED: Comes with clear guidance and tips for proper use, ensuring effective training and helping you get the most from your Brock String sessions ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B0190LOMCQ | | Brand Name | Brock String | | Color | White | | Customer Reviews | 4.5 4.5 out of 5 stars (2,110) | | Grip Material | Ethylene Vinyl Acetate Foam | | Handle Diameter | 38 month | | Handle Material | Ethylene Vinyl Acetate (EVA) | | Item Length | 6 Feet | | Item Weight | 0.02 Kilograms | | Manufacturer | Thera Systems LLC | | Material | Nylon, Polypropylene (PP) | | Other Special Features of the Product | Durable | | Recommended Uses For Product | Exercise and Fitness | | Target Audience | Adult | | UPC | 860007923074 722512440333 | | Unit Count | 1.00 Count | ## Product Details - **Brand:** Brock String - **Material:** Nylon, Polypropylene (PP) - **Recommended Uses For Product:** Exercise and Fitness - **Special Feature:** Durable - **Target Audience:** Adult ## Images ![Brock String, Vision Convergence Insufficiency Training Tool for Eye Muscle Strengthening, Focus Exercise and Agility - Image 1](https://m.media-amazon.com/images/I/513qIyNgBPL.jpg) ## Available Options This product comes in different **Size, Style** options. ## Questions & Answers **Q: Does it come with instructions?** A: Yes it comes with instructions both with the product and again digitally by email. **Q: does it improve my reaction time ?** A: We used these for my daughter to help her eyes work together. It was suggested by her vision therapist. I played around with it also and you do get better at focusing. **Q: Are the balls removable?** A: You could fairly easily remove them by untying the knot at the end of the string. However it may be tricky to put them back on. **Q: Can this be used in the bedroom?** A: Hi, Brock String is a vision performance training tool that can be used anywhere. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Good quality, easy to use *by J***B on December 2, 2025* It's good. The beads slide easily but stay where you put them. The string is easy to tie and untie. The string can be drawn taunt and bounce is easily controlled. ### ⭐⭐⭐⭐⭐ Great for eye convergence *by C***D on January 7, 2026* This string provides a means to work on convergence problems. I have excellent vision in my eyes but when I'm tired etc. I start seeing double --especially watching the television. I can see improvement after just a few sessions of the exercises. Hopefully before long I will no longer have the problem. Comes with instructions in English! They just don't indicate how long one should do them. If you get one, practice at least a few minutes at a time. ### ⭐⭐⭐⭐⭐ Good quality and helpful. *by A***R on November 17, 2025* It does exactly what it is supposed to do. It is of good quality and has been helpful. ## Frequently Bought Together - Brock String - Vision Convergence Training - Convergence Insufficiency Tool - Train Vision, Athletic Performance, and More!, White, 6 foot - Brock String 10 Foot Vision Convergence Training Tool - Train Vision, Improve Strength & Athletic Performance, and More! - DEFINEST Rechargeable LED Laser Headlamp with an Adjustable Waist Belt, for Sensorimotor Control Testing and Physical Therapy --- ## Why Shop on Desertcart? - πŸ›’ **Trusted by 1.3+ Million Shoppers** β€” Serving international shoppers since 2016 - 🌍 **Shop Globally** β€” Access 737+ million products across 21 categories - πŸ’° **No Hidden Fees** β€” All customs, duties, and taxes included in the price - πŸ”„ **15-Day Free Returns** β€” Hassle-free returns (30 days for PRO members) - πŸ”’ **Secure Payments** β€” Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** β€” Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.jp/products/24534652-brock-string-vision-convergence-insufficiency-training-tool-for-eye-muscle](https://www.desertcart.jp/products/24534652-brock-string-vision-convergence-insufficiency-training-tool-for-eye-muscle) --- *Product available on Desertcart Japan* *Store origin: JP* *Last updated: 2026-04-29*