Secure Safe Lock Cap System Hinged locking ball keeps the cap closed during centrifugation, minimizing evaporation and leakage. ^^ One-Handed Operation Snap the cap shut and slide the lock with minimal effort; designed for convenience and control. ^^ Smooth Surface Design Prevents glove tearing and improves handling comfort. ^^ Graduated 1.5 mL Tube Clear volume markings support accurate sample tracking and measurements. ^^ High-Quality Polypropylene Made from virgin resin for superior chemical resistance and sample protection.