# Haakaa Shell Wearable Collector Sizes Compared

Which size of the Haakaa Shell wearable silicone collector should a shopper buy?

The two listed sizes differ in capacity\. Haakaa Shell Wearable Silicone Breast Pump 2\.5 oz \(Pack of 6\): The pump capacity is 2\.5 oz\. Haakaa Shell Wearable Silicone Breast Pump 4 oz \(Pack of 6\): The pump capacity is 4 oz\. The checked facts do not say which size suits a particular need\.

### 1. [Haakaa Shell Wearable Silicone Breast Pump 2\.5 oz \(Pack of 6\)](/products/ucp/haakaausa-com/8532026491118) (sold by haakaausa\.com)

The pump capacity is 2\.5 oz\.

- Capacity: The pump capacity is 2\.5 oz\. (listing) <https://temp2016.myshopify.com/products.json>
- Suction: Suction strength is adjusted with the valve\. (listing) <https://temp2016.myshopify.com/products.json>
- Pouring: It has an easy\-pour outlet for transfer to a bottle or storage container\. (listing) <https://temp2016.myshopify.com/products.json>

### 2. [Haakaa Shell Wearable Silicone Breast Pump 4 oz \(Pack of 6\)](/products/ucp/haakaausa-com/8532027506926) (sold by haakaausa\.com)

The pump capacity is 4 oz\.

- Capacity: The pump capacity is 4 oz\. (listing) <https://temp2016.myshopify.com/products.json>
- Suction: Suction strength is adjusted with the valve\. (listing) <https://temp2016.myshopify.com/products.json>
- Pouring: It has an easy\-pour outlet for transfer to a bottle or storage container\. (listing) <https://temp2016.myshopify.com/products.json>

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Written 2026-10-20T01:05:41.933Z.

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