Hifiman RE-400* In-Ears for $49 each (regular, iOS, Android)

It’s Black Friday time for Hifiman products, and all three of their RE-400* in-ears are on sale for $49 with free shipping each. They are the wired no-mic/buttons model RE-400, the iOS-buttoned RE-400i and the Android/generally-buttoned RE-400a. They are separate listings so each model has its own set of reviews.