Sizing guide built into face mask packaging

This is a face mask for the ventilator. It comes in three sizes. A close fit is essential to reducing air leak and the device functioning well.

The edge of the bag has a useful custom sizing guide. You hold it up to the patient’s face so that you know which one to use.  

Very practicle. Very clear instructions. 

These masks are not cheap. It would have been in manufacture’s interest to not include this ruler, as then we would open and discard more incorrectly sized masks, or tolerate an improperly sized mask to cut costs. Good example of patient centred design.