Refurbished vs Replacement Unit
iPhone X, iOS 11.2
Apple sells refurbished units online in their refurbished store. They have information there on what their OEM refurbishment process entails. Refurbished devices bought from Apple have a standard one year warranty and are eligible for extended warranty.
A replacement unit is just that - a service unit used to replace a device. Every company sets aside some proportion of production as service units right from the factory, to provide stock for warranty replacements. Service units may be factory new, or they may have failed some factory inspection that required repair and so were pulled from the standard shipping line and end up (once fixed) in the service unit allotment.
Apple sells refurbished units online in their refurbished store. They have information there on what their OEM refurbishment process entails. Refurbished devices bought from Apple have a standard one year warranty and are eligible for extended warranty.
A replacement unit is just that - a service unit used to replace a device. Every company sets aside some proportion of production as service units right from the factory, to provide stock for warranty replacements. Service units may be factory new, or they may have failed some factory inspection that required repair and so were pulled from the standard shipping line and end up (once fixed) in the service unit allotment.
I believe, (I’m not 100% sure) that a replacement unit is new and was sent to replace a faulty unit. A refurbished unit is lightly used, fixed and verified to be in complete working order and is resold at a discount.
Refurbished vs Replacement Unit