Hi,I've purchased a Giro G9 Adult Snow Helmet. I wonder a thing. It has 15 vents, but 13 of them have vent plugs. The two vents at the back bottom (back of the neck) don't have plugs. Is it the standard or are the two vent plugs missing?

Tech Specs:

Material:

[Shell] Polycarbonate, [Liner] EPS 

Ventilation:

12 vents with included plugs 

Adjustability:

Adjustable strap with clip buckle 

Weight:

(13.5oz) 383g 

Recommended Use:

Freeride, all terrain 

Manufacturer Warranty:

1 year 

Country of Origin:

China