Redberry unbreakable flask 3L

Key Features

Durable stainless steel construction described as “unbreakable” — meaning the body is made of stainless steel rather than glass or brittle plastic liner.

Double-wall vacuum insulation (or “vacuum-sealed”) for good thermal retention of hot or cold beverages.

Available in a variety of capacities: typical sizes on the market include 2 L, 3 L, and even 4 L in some variants.

Leak-proof or secure screw-top lid designs in many specs — designed to prevent spills during transport.

Designed for everyday use in homes, offices, gatherings, events or even outdoor use.

Specifications & Performance (approximate)

Material: High-grade stainless steel (interior & exterior) for durability and rust resistance.

Capacity:

3 L model (e.g., “RSF 3001”) for family or group use.

Temperature retention: Many listings claim it will keep hot and cold beverages for extended hours (e.g., up to 24 hours) depending on usage.

Design: Easy-grip handle or heat-resistant handle in many models.

Finish: Metallic / polished stainless steel look (silver/metallic finish) typical.