Why Your Factory Requests 3mm "Extra Space" in Custom Tech Gift Foam Inserts (And Why It's Not Waste)

Buyers approve hand-trimmed prototype foam inserts with "perfect snug fit" and expect mass production to match exactly, without understanding that the 2-3mm clearance factories request is not wasted space—it's tolerance absorption buffer for CNC foam cutting (±1mm) and injection molding (±0.5mm) variations.