For most beverage bottle, raw material is used PET ( Polyethylene terephthalate), it has features of transparent, not poisonous, light etc. And internationally standard names it PCO, the 1810# means 28mm long neck preform, and 1881# means 28mm short neck preform.
PCO1881 only 3.8 grams, a preform weight averagely lighter than 1810 5-10%, for saving cost, beverage factory use 1881 often, although comsumer has to carefully open the shorten cap and drink, it donesn't matter, that's why in market beverage company sell 1810# bottle.
And for water bottle, the factory prefer to use 30mm preform, because water always cheaper than beverage, and it convenient to drink the water company use much diameter mouth 30mm instead of 28mm, although the 28mm PCO bottle still exist, but for most company choose 30/29mm bottle.
Rapily growing competitive market, company wonder top-mover beverage, who has to win comsumers' favorite. Not only the beverage itself, but also how they provide a design that attractive, easily open, to drink, lastly make people joyful.
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