The Chill-Its 5050B 2 Liter Replacement Bladder is compatible with the 5155 Hydration Pack (sold separately). The 2.0L (2000mL) bladder features a DualCap for easy no-spill filling with water or ice, plus an insulated tube to keep water cool in the heat.  

• COMPATIBLE WITH 5155 HYDRATION PACK – For clean on-the-go hydration (pack sold separately)
• CAPACITY – 2.0L // 2000mL
• HIGH-QUALITY THERMOPLASTIC – Durable to withstand wear and tear, no plastic taste or smell
• ANTIMICROBIAL BITE VALVE WITH COVER – Protects against contaminants for clean, safe hydration
• WIDE DUALCAP OPENING – 60mm cap inside 80mm cap for easy no-spill filling with water or ice
• INSULATED TUBE – Keeps water cool in the heat
• CLEANING KIT SOLD SEPARATELY – Chill-Its 5159 Hydration Pack Cleaning Kit