I started watching this and as someone else commented, yeah, things looked doable at the start and then got progressively more impressive and insane. It's clear

I started watching this and as someone else commented, yeah, things looked doable at the start and then got progressively more impressive and insane. It's clear they know what they're doing. From the extremely intricate tools for each and every specific step, to the screwdriver that tightens only the exact amount when putting things back together, to - what! - CNC milling off an entire component?! I was so impressed. Surely their day job must be in some way related to assembling this phone?