G'day Luke,

The opening of the Platypus Duolock Softbottle 2.0L is 32mm, but instead of a standard screw cap, it's a bayonet cap that clicks and twists to lock.
Unfortunately this means it wont be compatible with other standard drink bottle attachments.

G'day Amanda,

The Lifestraw Personal Water Filter has been designed so you can drink directly from the source. The base of the filter is too large to fit into the Duolock Softbottle. We'd recommend a wide mouth style bottle if you're wanting to scoop the water and carry it before drinking it through the Lifestraw.

G'day Addy,

Platypus don't specifically mention anything about popping in the freezer, but we can't think of any reason why it would be a problem. You'll just need to account for the expansion of the water, so don't fill it up too far.

G'day Tony,

Sorry mate but these won't work with the Platypus hydration systems. You'll need to grab one of their standard 2L bottles like this one here. We don't stock them currently but we're happy to chase on up for you. Just email us at service@snowys.com.au  and we'll follow it up for you. 

G'day Alara,

You can use your Platy bottles with other liquids, just make sure you clean it thoroughly after each use to prevent bacteria from growing in it, including the cap. Don't, whatever you do, use it for carbonated beverages like beer or soft drinks though. 

G'day Tony,

Sorry for contradicting ourselves, we've fixed it up now. The Platypus Duolock Softbottle 2.0L weighs 50g.