glossary
What is a closed-system pump?
Quick answer: A closed-system pump has a barrier (backflow protector) between milk and the motor tubing, so milk and moisture can never enter the mechanism. An open system lacks that barrier.
In practice
Closed systems are the modern default and the only kind that should ever be shared or bought secondhand, and even then with fresh personal parts. Barrier membranes still wear out; a cracked backflow protector quietly bleeds suction like a worn duckbill.
In Milk First
Log any session in two taps, backdate the ones you forgot, and let the 7-day average chart answer supply questions with real numbers. Every pump files its milk into the stash automatically.
Milk First speaks this whole language for you: seshes logged in two taps, every bag on its correct clock.
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