Bacteriostatic water (bac water)

Bacteriostatic water is sterile water containing 0.9% benzyl alcohol as a preservative. The benzyl alcohol prevents bacterial growth in the multi-dose vial after you puncture the rubber stopper. Standard reconstituted peptides keep for ~28 days at 2-8°C in bac water. Plain sterile water (without the preservative) is single-use only — you'd have to throw out the vial after one draw. Bac water comes in 30mL multi-use vials and costs about $4 on Amazon.