Tetra Etiquette Straw

I made a great discovery today! (^_^)

This morning I drank a pack of juice called "Jyu-jitsu Yasai (full of
vegetables)" made by Ito-en.

This contains 20 vegetables (carrots, spinach, colored sugar beets,
lettuce, red sweet pepper, kidney beans, celery, broccoli, kales,
pumpkins, green peppers, asparaguses, napa cabbages, Komatsu-na,
Ashita-ba, parsley, watercresses, cabbages, radishes, honewort) and
three fruits (apples, lemons, grapes). Moreover, 2600 micro-g of
beta-carotene is included in the 100g of this juice!!!

This is not so important here... (^_^;;;
Anyway, the straw which sticks to this pack is a great straw... It has
a silencer and the name is "Tetra Etiquette Straw"! Though it only
has a streak along the straw...

I noticed it this morning for the first time in my life! But this
seems to exist for about five years... so many persons have already
known this???

By the way, it is silent when you leave your mouth from the straw, not
when you are drinking.

But why "Tetra"? Since the cut of the straw is like a quadrangle???