Quick Answer

The eufy S1 Pro and S2 Pro use different accessories. The S1 Pro has its own duckbill valves, while the S2 Pro is compatible with specific milk containers and diaphragms. Check your pump model before buying parts.

Why Model Matters for Accessories

eufy designed the S1 Pro and S2 Pro as distinct wearable pumps with different form factors. That means accessories like duckbill valves, milk containers, and diaphragms are not interchangeable between the two models. Using the wrong part can affect suction, fit, or milk flow.

The S1 Pro comes with HeatFlow™ technology and a wireless charging case, while the S2 Pro has its own set of compatible accessories. Understanding which parts work with your pump saves you time and frustration.

Trade-Offs at a Glance

  • S1 Pro Duckbill Valves (4-Pack): Designed exclusively for the S1 Pro pump. They help maintain suction and prevent clogs. Not compatible with S2 Pro.
  • S2 Pro Milk Container (5 oz, 2-Pack): Fits the S2 and S2 Pro only. Made from food-grade, BPA-free materials. Dishwasher safe for easy cleaning.
  • S2 Pro Diaphragm (2-Pack): Exclusively for S2 and S2 Pro pumps. Delivers consistent suction and prevents milk from entering the motor. Made from soft, baby-safe silicone. Replace diaphragms regularly to maintain pump performance and hygiene.

Accessories at a Glance

  • eufy Breast Pump S1 Pro & Duckbill Valves (4-Pack): The eufy Breast Pump S1 Pro & Duckbill Valves (4-Pack) includes duckbill valves designed specifically for the S1 Pro pump. These valves are essential for maintaining proper suction and preventing milk backflow, and they are not compatible with the S2 Pro.

    eufy Breast Pump S1 Pro & Duckbill Valves (4-Pack)

    eufy Breast Pump S1 Pro & Duckbill Valves (4-Pack)

  • eufy Milk Container (2-Pack, 5 oz) for Breast Pump S2 / S2 Pro: The eufy Milk Container (2-Pack, 5 oz) is exclusively compatible with the eufy S2 and S2 Pro pumps. If you own an S2 Pro, this container offers a safe, BPA-free storage option that fits the pump directly, but it won't work with the S1 Pro.

    eufy Milk Container (2-Pack, 5 oz) for Breast Pump S2 / S2 Pro

    eufy Milk Container (2-Pack, 5 oz) for Breast Pump S2 / S2 Pro

Which Accessories Are Right for You?

Best for

  • S1 Pro owners needing replacement duckbill valves
  • S2 Pro owners needing milk containers or diaphragms

Not for

  • S1 Pro owners buying S2 Pro accessories (they won't fit)
  • S2 Pro owners buying S1 Pro duckbill valves (incompatible)