noun-modifying (irregular)
SIM-free; unlocked
Describes a mobile phone that is not tied to a specific carrier and can be used with any compatible SIM card.
SIMフリーのスマホを買ったので、格安SIMを使っています。
I bought a SIM-free smartphone, so I'm using a budget SIM card.
海外旅行のときはSIMフリー端末が便利です。
A SIM-free device is convenient when traveling abroad.