I'm not entirely sure which model you mean, so I'll just answer for both. [br]
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A 2015 13" MacBook Pro or Air still has a removable hard drive. They use a proprietary form factor SSD, but it is upgradable. [br]
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A 2015 12" MacBook Retina (this is the one with just One USB C port plus a headphone jack, and no other ports) has soldered on storage and cannot be ungraded without some serious soldering skills.
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A 2015 12" MacBook Retina (this is the one with just One USB C port plus a headphone jack, and no other ports) has soldered on storage and cannot be upgraded without some serious soldering skills.
I'm not entirely sure which model you mean, so I'll just answer for both. [br]
[br]
A 2015 13" MacBook Pro or Air still has a removable hard drive. They use a proprietary form factor SSD, but it is upgradable. [br]
[br]
A 2015 12" MacBook Retina (this is the one with just One USB C port plus a headphone jack, and no other ports) has soldered on storage and cannot be ungraded without some serious soldering skills.