HI7004L is a premium-quality pH 4.01 calibration solution. Hanna calibration buffers have the lot number and expiration date clearly marked on the label. Each bottle is airtight and features a tamper-proof seal to help ensure the quality and integrity of the solution. Hanna’s line of calibration buffers is specially formulated to have a shelf life of 5 years from the date of manufacture when unopened.

• Color-coded label for easy pH buffer value identification
• Accuracy of ±0.01 pH at 25 °C
• Temperature chart showing the actual pH value at various temperatures printed on each bottle