I am the buyer who bought the spirulina through post
Save my time and transport cost.
The postage is 80cents(non-standard mail) for my purchase of 50g worth of spirulina excluding the ziglock bag and envelop.
Singpost
To round up, its $1.
My MRT fare to and back cost more than that..
But again, like Nikel mention, someone will have to bear the risk in case Singpost lose the mail (although rare) unless you opt for registered mail.