Double check valve - Wikipedia

Item 2089 - Stop Potential Error Double Check Labels

Double-Check - Usage & Meaning

Are You a Double Checker? - Nancy Friedman

Independent Double Check

Behavior Poster: Double Check Your Work

Double check before the checkpoint

A Randomized Controlled Trial on the Effect of a Double Check on the Detection of Medication Errors - ScienceDirect

DOUBLE CHECK

Seen done accepted checked double - User Interface & Gesture Icons

Label reads: Double Check, Labels are Yellow with Black text, 1000/EA