Blog
How to Read Gummi Codes: Designation Structure, Prefixes, Suffixes and Real Examples
Practical guide to understand Gummi coupling nomenclature. Decode codes and designations to identify the correct coupling for your application.
Technical team at MR Accesorios Industriales · Updated on September 29, 2026

Introduction to Gummi Nomenclature
Gummi couplings are recognized in Argentine industry for their robustness and reliability. To select the right coupling, it is essential to understand how their codes are structured. In this guide, we explain the logic behind Gummi designations, so you can interpret any reference and order the correct replacement.
Gummi nomenclature follows a logical pattern combining letters and numbers. Each part of the code provides information about the coupling type, size, and specific characteristics. Knowing this structure allows you to quickly identify the product and avoid ordering errors.
As an official Gummi distributor, at MR Accesorios Industriales we work with couplings and help you decipher any code. If you have doubts, you can consult us with the reference or a photo of the part.
General Structure of a Gummi Code
A typical Gummi code consists of an alphabetic prefix and a number. The prefix indicates the series or type of coupling, while the number generally refers to the size or shaft diameter. For example, in codes A-50, A-20, and A-90, the letter A identifies a specific series and the number corresponds to a nominal size.
It is important not to confuse the number with a direct measurement in millimeters; it is usually a relative size indicator within the series. To know the exact dimensions, always consult the technical catalog or product data sheet.
In addition to the prefix and number, some codes may include suffixes indicating variants, such as different elastomer materials or surface treatments. These suffixes are added after the main number, separated by a hyphen or without a separator.
Common Prefixes in Gummi Couplings
In the Gummi coupling line, the most common prefixes are letters such as A, B, C, etc., which designate different series. Each series has particular design characteristics, torque capacity, and recommended applications. For example, the A series is usually for general use, while other series may be oriented to high-power applications or special requirements.
Knowing the prefix allows you to quickly identify the coupling type and its compatibility with your equipment. If you are not sure which series corresponds to your application, you can consult us and we will guide you based on your machine data.
At MR we sell Gummi couplings, including the most used series in industry. We work with references from the official catalog and quote any code you need.
Meaning of Numbers in Codes
The number following the prefix in a Gummi code is related to the coupling size. Generally, the higher the number, the larger the shaft diameter and torque transmission capacity. For example, an A-90 coupling is larger than an A-50, and this in turn is larger than an A-20.
However, the number is not a direct measurement; it is a size code that corresponds to specific dimensions in the manufacturer's tables. To select the correct coupling, it is necessary to verify the shaft diameter and required torque, and then choose the code that meets those parameters.
If you have the code of an existing coupling, you can use it to order an exact replacement. If you don't have it, with the shaft measurements and application we can help you identify the appropriate code.
Suffixes and Variants in Designations
Some Gummi codes include suffixes that indicate specific variants. These suffixes may refer to the type of elastomer, the presence of tapered bushings, special treatments, or versions for particular environments. For example, a suffix like -R could indicate a reinforced version, although you should always confirm with the catalog.
It is crucial to respect the suffixes when ordering a replacement, as an incorrect variant may not be compatible with your installation. If you have doubts about the meaning of a suffix, consult us and we will clarify it.
At MR we work with all available variants of Gummi couplings and advise you to choose the correct option. Send us the complete code or a photo of the identification plate and we will quote the replacement.
Real Examples of Gummi Codes
To illustrate the nomenclature, let's look at some examples of Gummi codes we sell: A-50, A-20, and A-90. These codes belong to the A series and differ by size number. The A-20 is the smallest of the three, suitable for light applications; the A-50 is medium-sized; and the A-90 is the largest, for higher torque demands.
These examples show how the combination of letter and number allows quick identification of the coupling type and size. When requesting a quote, it is always advisable to indicate the complete code, as it appears on the part or in the equipment manual.
If you cannot find the exact code, you can send us a photo of the coupling with a ruler or caliper next to it, and we will help you identify it. You can also provide the shaft measurements and motor power to select the appropriate coupling.
Tips for Ordering Your Gummi Coupling
When requesting a Gummi coupling, it is important to have as much information as possible on hand: complete code, shaft measurements, motor power and speed, and operating conditions. With this data, we can quote the correct coupling without error.
If you don't have the code, don't worry: with a clear photo of the part and some basic measurements, we can identify the model. It is also useful to know the make and model of the machine where the coupling is mounted.
At MR Accesorios Industriales, as an official Gummi distributor, we offer technical advice so you choose the right coupling. Contact us via WhatsApp or email and we will respond promptly with a quote.
Frequently asked questions
How do you read a Gummi coupling code?
A Gummi code consists of an alphabetic prefix indicating the series and a number indicating the size. For example, in A-50, the A is the series and 50 is the size. Some codes may include suffixes for specific variants.
What does the letter in Gummi codes mean?
The letter at the beginning of the code identifies the series or type of coupling. Each series has particular design and application characteristics. For example, the A series is for general use, but there are other series for specific requirements.
Is the number in the Gummi code a measurement in millimeters?
No, the number is a relative size indicator within the series. It does not directly correspond to a measurement in millimeters. To know the exact dimensions, consult the manufacturer's tables.
Where can I get Gummi couplings in Argentina?
At MR Accesorios Industriales, official Gummi distributor in Buenos Aires, Argentina. We sell couplings and advise you to choose the right one. You can consult us via WhatsApp or email.
What do I do if I can't find the code for my Gummi coupling?
If you don't have the code, you can send us a photo of the coupling with a measurement reference (such as a ruler) and the shaft measurements. With that information, we identify the model and quote the replacement.
Products with photos in the catalogue
Keep reading
- GUMMI Couplings: Vibration Absorption and Reliable Power Transmission for Industry
GUMMI elastic couplings absorb vibrations and misalignments, protect machinery, and ensure reliable power transmission. Learn about their configurations and how to choose the right model.
- Gummi Couplings: applications, selection and maintenance to make them last
Discover where Gummi couplings are used, how to choose the right model for your application and the best assembly and maintenance practices to extend their service life.
- Tsubaki industrial chains: quality, durability and performance for demanding applications
Discover the types of Tsubaki chains we supply: roller, conveyor, leaf, freewheels, couplings and torque limiters. We help you choose the right one for your application.
Continue here
Need a quote?
Send us the code, size or a photo of the part and we'll quote you shortly.

