Reliable Replacement Lid for Optima Flasks This spare lid is compatible with Milton Optima Thermosteel flasks and fits 350ml, 420ml, 470ml, and 500ml capacities, making it a perfect replacement for lost or damaged caps. Leak-Proof & Secure Fit Designed with precision threading, the lid ensures a tight, leak-proof seal, preventing spills while carrying the bottle in bags or backpacks. Safe & Long-Lasting Material Manufactured using BPA-free, food-grade plastic, safe for both hot and cold beverages and suitable for everyday use. Easy-Twist Convenience The smooth twist-open mechanism offers hassle-free use while helping maintain the temperature efficiency of vacuum-insulated Thermosteel bottles. ⚠️ Note: This product includes only the spare lid. Bottle not included. Keep your favourite Milton Optima Thermosteel flask properly sealed with this premium replacement lid. Designed for perfect compatibility with 350ml, 420ml, 470ml, and 500ml Optima Thermosteel flasks, this spare lid ensures your beverages stay secure and at the desired temperature. The lid features a sleek grey and silver design that matches the flask's aesthetic while offering practical functionality. Its easy-twist mechanism provides a leak-proof seal, making it ideal for daily use, travel, or outdoor activities. The ergonomic design allows for comfortable handling and quick access to your beverages. Made with durable materials, this replacement cap maintains the thermal efficiency of your flask while preventing any unwanted spills. Whether you need a replacement for a lost lid or want a spare one handy, this authentic Milton lid is the perfect solution to extend the life of your Optima Thermosteel flask.

• UNIVERSAL COMPATIBILITY: Designed to fit multiple Milton Optima Thermosteel flask sizes including 350ml, 420ml, 470ml and 500ml models
• LEAK-PROOF DESIGN: Features a secure easy-twist mechanism that creates an airtight seal to prevent spills and leaks
• DURABLE CONSTRUCTION: Made with high-quality stainless steel top and sturdy grey thermoplastic base for long-lasting performance
• EASY REPLACEMENT: Simple twist-and-lock mechanism makes it quick and convenient to replace your old flask lid
• PRACTICAL DESIGN: Ribbed grip pattern on the lid ensures comfortable handling and secure tightening