Size Finder

Which bac water size should I buy?

An opened vial is usually discarded 28 days after its first use. Buy a vial you finish inside 28 days and nothing goes to waste. Tell us your use — the finder picks the size and the number of boxes (10 vials a box; 30 mL: 25).

Your usage

Bac water you draw (mL)

Per

Cover

Example: reconstituting four peptide vials a week with 1.5 mL each = 6 mL per week = 24 mL per 28 days. An opened multi-dose vial is usually discarded 28 days after the first puncture, so a vial bigger than your 28-day use leaves water you throw away.

Recommended

10 mL · 1 box of 10 vials

You need 8 vials — $15.00

Uses 24 mL per 28 days · each vial lasts 11.67 days · nothing discarded · 2 spare vials

All sizes for this usage

3 mL · 24 vials needed · lasts 3.5 d each

3 boxes of 10 vials · no waste

$39.00

5 mL · 15 vials needed · lasts 5.83 d each

2 boxes of 10 vials · no waste

$28.00

10 mL · 8 vials needed · lasts 11.67 d each

1 box of 10 vials · no waste

$15.00

30 mL · 3 vials needed · lasts 28 d each

1 box of 25 vials · 18 mL discarded

$155.00

How the finder works

Each vial lasts until it is empty or 28 days after you open it, whichever comes first.
Vials needed = the period you want to cover ÷ how long one vial lasts, rounded up.
Water left in a vial at day 28 is counted as waste.
Vials are sold by the box: the finder rounds up to whole boxes and, with prices shown, picks the size that costs the least.

The finder works in millilitres of diluent only. It does not give doses. The 28-day convention comes from guidance on opened multi-dose vials (CDC); follow your lot's label if it states another period.

Questions

I use very little. Which size?

Below 3 mL in 28 days, the 3 mL vial wastes the least. You will still discard what is left on day 28.

Is a big vial ever cheaper overall?

Only when you finish it within 28 days. Otherwise you pay for water you throw away.

Why does it suggest more vials than I need?

We sell by the box only (10 vials; 30 mL: 25). The finder rounds up to whole boxes; the extra vials keep until their expiry date while unopened.