# How-to Attach Custom Values (MMS) to SMS Messages
**Introduction**
Custom values offer a dynamic way to enhance your workflows in Gymini. This guide will walk you through the process of using custom values to send MMS messages within your workflows.
**Overview**
Custom values are versatile tools that can be used to integrate snapshots and preferred workflows. They provide a straightforward setup, making your automation processes more scalable and engaging.
**Topics Covered:**
* Attaching Custom Values URLs to SMS messages
* Troubleshooting common issues
* Understanding MMS size limits for different carriers
* Supported file types for MMS via SMS
* Solutions when custom values don't work as expected
**Attaching Custom Values URLs to SMS Messages:**
**Step 1: Setting Up Your Custom Value URL**
1. Navigate to **Location Settings**.
2. Click on **Custom Values**.
3. Select **+ Add Custom Value**.
4. Enter the desired MMS URL.
**Step 2: Integrating the Custom Value in Your Workflow**
1. Open the workflow where you wish to send the MMS.
2. Ensure you attach the custom value as an attachment.
3. Copy and paste the value into the appropriate field.
> **Note:** Different carriers have specific requirements for MMS sizes. For detailed size requirements by carrier, refer to the section below titled "What is the maximum MMS size when sending SMS?"
**Troubleshooting:**
**1. What is the maximum MMS size when sending SMS?**
| **Carrier** | **Long code MMS attachment size** | **Toll-Free MMS attachment size** | **Shortcode MMS attachment size** |
| ----------- | --------------------------------- | --------------------------------- | --------------------------------- |
| AT\&T | 0.6 MB | 0.6 MB | 0.6 MB |
| Sprint | 1.4 MB | 0.6 MB | 1.4 MB |
| T-mobile | 1.5 MB | 0.6 MB | 1.0 MB |
| Verizon | 0.675 MB | 0.6 MB | 1.2 MB |
**2. What are the supported file types for MMS when sending via SMS?**
* jpeg
* png
* gif
**3. My custom value does not work when the message is sent. What should I do?**
* Ensure there are no spaces in your custom value URL. You can test this by adding it to a dummy funnel and previewing the page. If the MMS appears, the custom value is functional.
* Verify that the MMS URL meets the size requirement for the specified carrier (refer to the table above for size requirements).
**Conclusion:**
Custom values in Gymini workflows provide a powerful way to enhance your SMS messaging capabilities with MMS. By understanding the steps and troubleshooting common issues, you can effectively leverage this feature to improve your communication strategies.
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