--- title: Ratio Four Materials Breakdown description: Curious about what materials are used in the youngest sibling of the Ratio family? Here's a closer look at how we thoughtfully selected each component for performance, safety, and longevity. --- [Skip to content](https://help.ratiocoffee.com/ratio-four-materials-breakdown#main-content) English Show submenu for translations ![b8418dc3-0886-4e57-a609-b76b4a600d63.png\]](https://help.ratiocoffee.com/hs-fs/hubfs/b8418dc3-0886-4e57-a609-b76b4a600d63.png?height=42&name=b8418dc3-0886-4e57-a609-b76b4a600d63.png) - [Choosing the Right Ratio Machine](https://help.ratiocoffee.com/choosing-the-right-ratio-machine) - [Warranty Form](https://ratiocoffee.com/pages/warranty-request-form) - [Return Form](https://ratiocoffee.com/pages/return-request-form) Open main navigation Close main navigation - [Choosing the Right Ratio Machine](https://help.ratiocoffee.com/choosing-the-right-ratio-machine) - [Warranty Form](https://ratiocoffee.com/pages/warranty-request-form) - [Return Form](https://ratiocoffee.com/pages/return-request-form) - English Show submenu for translations - [Home](https://ratiocoffee.com/) [Home](https://ratiocoffee.com/) How can we help? - There are no suggestions because the search field is empty. 1. [Help Center](https://help.ratiocoffee.com/?hsLang=en) 2. [Coffee Guides & Education](https://help.ratiocoffee.com/coffee-guides-education-1?hsLang=en) 3. [Materials](https://help.ratiocoffee.com/coffee-guides-education-1?hsLang=en#materials) # Ratio Four Materials Breakdown ## Curious about what materials are used in the youngest sibling of the Ratio family? Here's a closer look at how we thoughtfully selected each component for performance, safety, and longevity. Curious to learn about our approach to plastics and how we pick materials for our machines? Please click here! - Water Tank — constructed of Eastman Tritan TX2001, a high-quality, shatter-resistant, BPA-free polymer plastic. **No hot water contact**. - [Click here for detailed information about the water tanks we use!](https://help.ratiocoffee.com/ratios-approach-to-materials?hsLang=en) - Water Lines — FDA-approved silicone. **Hot water contact**. - Shower Head — 304 stainless steel. **Hot water contact**. - Heating Element — crafted from the same aluminum as the Ratio Six and Ratio Eight's heater, in a more compact size. **Hot water contact**. - Brew Basket — constructed from a BPA-free polymer plastic. **Hot water/coffee contact when in use**. - Looking to minimize plastic and hot water contact as much as possible with the Ratio Four? You have the freedom to swap out the Ratio Four's filter basket for a pour-over dripper constructed of a material of your choice! We recommend the Hario V60 Size 02 in metal or glass. If you prefer ceramic, we would suggest the Size 01 Hario V60 or the Kalita Wave. - Glass Carafe and Heat Lid — hand-blown borosilicate glass; carafe heat lid features a thin silicone seal which helps it secure in place and retain the temperature of your coffee. **Hot water/coffee contact**. - Internal structure, water tank dock, and water line flexible cover — Metal. **No hot water contact**. - [Getting Started](https://help.ratiocoffee.com/getting-started?hsLang=en#main-content) - [Eight Series 2](https://help.ratiocoffee.com/getting-started?hsLang=en#eight-series-2) - [Six](https://help.ratiocoffee.com/getting-started?hsLang=en#six) - [Four](https://help.ratiocoffee.com/getting-started?hsLang=en#four) - [Eight Original](https://help.ratiocoffee.com/getting-started?hsLang=en#eight-original) - [Ratio Rewards](https://help.ratiocoffee.com/getting-started?hsLang=en#ratio-rewards) - [Coffee Guides & Education](https://help.ratiocoffee.com/coffee-guides-education-1?hsLang=en#main-content) - [Water](https://help.ratiocoffee.com/coffee-guides-education-1?hsLang=en#water) - [Grind](https://help.ratiocoffee.com/coffee-guides-education-1?hsLang=en#grind) - [Coffee](https://help.ratiocoffee.com/coffee-guides-education-1?hsLang=en#coffee) - [Grinders](https://help.ratiocoffee.com/coffee-guides-education-1?hsLang=en#grinders) - [Dose](https://help.ratiocoffee.com/coffee-guides-education-1?hsLang=en#dose) - [Maintenance](https://help.ratiocoffee.com/coffee-guides-education-1?hsLang=en#maintenance) - [Materials](https://help.ratiocoffee.com/coffee-guides-education-1?hsLang=en#materials) - [Maintenance](https://help.ratiocoffee.com/maintenance?hsLang=en#main-content) - [Cleaning](https://help.ratiocoffee.com/maintenance?hsLang=en#cleaning) - [Ratio Eight Series 2](https://help.ratiocoffee.com/maintenance?hsLang=en#ratio-eight-series-2) - [Ratio Eight Original](https://help.ratiocoffee.com/maintenance?hsLang=en#ratio-eight-original) - [Ratio Six](https://help.ratiocoffee.com/maintenance?hsLang=en#ratio-six) - [Ratio Four](https://help.ratiocoffee.com/maintenance?hsLang=en#ratio-four) - [Grinders](https://help.ratiocoffee.com/maintenance?hsLang=en#grinders) - [Warranty](https://help.ratiocoffee.com/warranty?hsLang=en) - [Returns](https://help.ratiocoffee.com/returns?hsLang=en) - [Troubleshooting](https://help.ratiocoffee.com/troubleshooting?hsLang=en#main-content) - [Eight Original](https://help.ratiocoffee.com/troubleshooting?hsLang=en#eight-original) - [Eight Series 2](https://help.ratiocoffee.com/troubleshooting?hsLang=en#eight-series-2) - [Ratio Six](https://help.ratiocoffee.com/troubleshooting?hsLang=en#ratio-six) - [Ratio Four](https://help.ratiocoffee.com/troubleshooting?hsLang=en#ratio-four) - [Accessories](https://help.ratiocoffee.com/troubleshooting?hsLang=en#accessories) - [Choosing the Right Ratio Machine](https://help.ratiocoffee.com/choosing-the-right-ratio-machine) - [Warranty Form](https://ratiocoffee.com/pages/warranty-request-form) - [Return Form](https://ratiocoffee.com/pages/return-request-form) [![Chill listening crop-3](https://help.ratiocoffee.com/hs-fs/hubfs/b8418dc3-0886-4e57-a609-b76b4a600d63.png?width=100&height=25&name=b8418dc3-0886-4e57-a609-b76b4a600d63.png "Chill listening crop-3")](https://ratiocoffee.com/) Help Center Copyright © 2026, Ratio