













GK-3494 Open Gear Bass Guitar Machine Heads with 1:20 Ratio Tuners
SKU:GK-3494CR-2R2L
PRODUCT DESCRIPTION
Upgrade your bass with open gear tuning machines designed for smooth and precise tuning adjustment. The Guyker GK-3494 bass tuning machines feature a 1:20 gear ratio and multiple layout options for bass repair, replacement, and custom build projects.
Key Features
- Open gear bass tuner design: A classic open gear structure suitable for bass hardware replacement and custom builds.
- 1:20 gear ratio: Provides fine tuning control for accurate string adjustment.
- Multiple layout options: Available in 2R+2L, 4R, 4L, 1R, and 1L options depending on the selected variant.
- Fitment reminder: Please check the 13.7 mm peg hole requirement, 9 mm string post diameter, bushing type, and mounting position before ordering.
Technical Specifications
| SKU / Model | GK-3494 |
| Product Type | Open Gear Bass Tuning Machines |
| Suitable For | Bass guitar replacement and custom build projects |
| Layout Options | 2R+2L, 4R, 4L, 1R, 1L |
| Gear Ratio | 1:20 |
| Peg Hole Requirement | 13.7 mm |
| String Post Overall Height | 25 mm |
| String Post Diameter | 9 mm |
| String Thru Hole Center Height | 32 mm |
| Bushing Type | Screw-in hex head |
| Weight | 68.8 g per piece / 346 g per set |
| Finish Options | Chrome, Black, Gold |
| Package Includes | Bass tuning machines, threaded bushings, mounting screws, ferrules |
Compatibility Notes
Important: Please confirm your bass guitar’s peg hole diameter, string post diameter, bushing type, tuner footprint, and mounting screw position before ordering. Minor modification may be required depending on the bass model, production year, or existing hardware.
Package Includes
- Package quantity varies depending on the selected layout option.
- 2R+2L option: 2 x right-side bass tuning machines and 2 x left-side bass tuning machines with matching hardware
- 4R option: 4 x right-side bass tuning machines with matching hardware
- 4L option: 4 x left-side bass tuning machines with matching hardware
- 1R option: 1 x right-side bass tuning machine with matching hardware
- 1L option: 1 x left-side bass tuning machine with matching hardware
Installation Note
Before installation: Compare all dimensions with your original bass tuners, including the 13.7 mm peg hole requirement, 9 mm string post diameter, and mounting screw location.
Product Video
Watch the product video below for a closer look at the tuning machines and installation reference.
Size Reference
Important: Please refer to the size chart below and compare all dimensions with your original part before ordering.

VIDEO
FAQS
Do you class a reverse headstock guitar as a left hand guitar?
How do I determine the right size/fit for a specific accessory?
Can you provide more details about the materials used in your products?
At Guyker, we prioritize the use of high-quality materials to ensure the durability and performance of our products. While the specific materials used may vary depending on the accessory, we commonly utilize materials such as:
■ Metals: We often use materials like stainless steel, aluminum, and brass for hardware, bridges, and other metal components.
■ Plastics: Certain accessories may incorporate durable and impact-resistant plastics such as ABS or polycarbonate for knobs, pickguards, and other components.
■ Woods: Some accessories, like guitar knobs or picks, may be made from various types of wood, including rosewood, ebony, or maple.
For more detailed information about the materials used in a specific product, we recommend reviewing the product descriptions or reaching out to our customer support team at [support@guyker.com] for further clarification.
Do you offer international shipping?
Yes, we offer international shipping to customers worldwide. When placing your order, please ensure that you provide accurate international shipping information, including your complete address and contact details.
Please note that international shipping may be subject to customs duties, taxes, and additional fees imposed by the destination country. These charges are the responsibility of the recipient and may vary depending on the country's customs policies.
What is your process for returning or exchanging a product?
To initiate a return or exchange, please follow these steps:
■ Contact our customer support team at [support@guyker.com] or visit our website's Returns/Exchanges page.
■ Provide your order details and the reason for the return or exchange.
■ Our customer support team will guide you through the process and provide you with a return/exchange authorization if applicable.
■ Follow the instructions provided, including packaging the product securely and attaching the necessary labels or documentation.
■ Ship the product back to us using a traceable and insured shipping method.
■ Once we receive the returned product and verify its condition, we will process the return or exchange accordingly.
Can I return or exchange a product if it's been used?
In most cases, products that have been used or show signs of wear may not be eligible for return or exchange unless there is a defect or error on our part. We recommend reviewing our specific return/exchange policy or contacting our customer support team at [support@guyker.com] to determine the eligibility of your particular product.
Do I need to cover the return shipping costs?
The responsibility for return shipping costs may vary depending on the reason for the return or exchange. In some cases, such as if the product is defective or if we made an error, we will provide a prepaid shipping label or reimburse your return shipping costs. However, if the return or exchange is due to a change of mind or a non-defective product, you may be responsible for the return shipping costs. We recommend reviewing our return/exchange policy or contacting our customer support team at [support@guyker.com] for specific details regarding return shipping costs.

GK-3494 Open Gear Bass Guitar Machine Heads with 1:20 Ratio Tuners
If you have any questions, you are always welcome to contact us. We'll get back to you as soon as possible, within 24 hours on weekdays.
-
Shipping Information
Use this text to answer questions in as much detail as possible for your customers.
-
Customer Support
Use this text to answer questions in as much detail as possible for your customers.
-
FAQ’s
Use this text to answer questions in as much detail as possible for your customers.
-
Contact Us
Use this text to answer questions in as much detail as possible for your customers.

4 interest-free payments.