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    Vacuum Flask Stem BL

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    A new stainless steel bottle you’ll want to take with you wherever you go,
    whether commuting or climbing a snowy mountain.

    The FLASKER is one of Rivers’ most popular products.
    The FLASKER is the first vacuum flask developed by Rivers, and is notable for its design,
    which goes against the times by not merely going along with typical cylindrical designs.

    However, we have decided that once our current inventory is depleted, we will discontinue the sale of this product.
    (In fact, our stock is almost completely gone.)
    We would have liked to continue selling this product, but are unable to do so due to circumstances out of our control.
    One year ago, we decided to develop a new flask.
    Perhaps it was only natural that we carried on the FLASKER design of our previous product.
    The fruit of our development work was the new STEM.
    Because it is a follow-up to a popular product, we worked to make it even better.

    Lighter is better
    “The lighter a flask, the better its heat and cold insulation properties.”

    When people hear this, they are often surprised.

    “Isn’t it the other way round?” they ask.

    To be sure, vacuum flasks have an image of securely locking in heat behind thick steel walls.
    The reality, however, is that lighter vacuum flasks work better.

    Setting aside technically complex reasons,
    what could be better than a lightweight flask with superb heat and cold insulation performance?

    Let’s compare the weights of our previous product, the FLASKER (420ml),

    and our new product, the STEM (500ml).


    Despite holding 20% more (80ml), it weighs roughly 25% less.
    So just how light is 200g?

    It’s about the weight of a smartphone.

    High thermo function for overwhelming heat and cold insulation

    So the STEM was designed to be ultralight, but we didn’t stop there.
    We also used all the technologies needed for modern stainless steel development.

    One of those technologies was the use of copper plating for the interior of the vacuum compartment.
    This blocks heat transfer due to thermal radiation, further improving the flask’s heat-retention capabilities.

    What is thermal radiation?
    Thermal radiation is heat that is conveyed by far-infrared rays.
    It is propagated even through spaces with no air. Outer space is a vacuum,
    but heat from the Sun is conveyed to the Earth through thermal radiation.

    The heat from flask contents also tries to escape through thermal radiation, but copper plating blocks it.

    Last winter, we performed a field test.
    We brought coffee that was freshly brewed in the morning to a snowy mountain in a STEM.
    In the evening, when we opened the STEM, steam rose out of the top.
    It is so good at retaining heat that those who can’t handle really hot drinks should probably
    let them cool a little before pouring them into the STEM.

    Resistant to staining, easy to eliminate odors.

    The interior stainless steel surfaces of bottles have tiny bumps and indentations, too small to see with the naked eye,
    that can easily become dirty. STEM is electropolished to create a smooth, gleaming surface.
    This helps it avoid becoming dirty, and reduces odor buildup from drinks.
    Customers love how hygienic it is.

    Use it as a simple flask or as outdoor gear.
    The STEM comes in two designs: a simple standard design and a design with a dedicated strap, called a bottle leash.
    You can use the bottle leash to hang the STEM from your bag, as a handle when carrying the STEM by hand,
    or to make it easy to hold when the outer lid is open.
    Please note that this tremendously useful part cannot be attached to a standard model STEM,
    so you can’t buy and use a separate leash later.

    – Material: Stainless steel (Bottle) / Polypropylene (Lid, Plug)/ Silicone rubber (Lid, Plug),
    Stainless Steel (Ring) / polypropylene (Leash,Hook) / Polyester (Velcro,Tag)
    – Capacity : 500ml
    – Thermal insulation effect : 73°C (6hours)
    – Cold insulation effect : 7°C (6hours)
    – Size : W80mm x D70mm x H225mm
    – Weight : 230g
    (Not suitable for: microwave, dishwasher,dryer.)

    What people say about The Den Manila

    A hole in the wall coffee shop that can be found in Escolta, The menu is in fact interesting and I went for the Bergs paired with Toast topped with Nutella Spread. Fell in love with the grilled cheese with tomato dip. The quality of the bread is good and the cheese is just as great.

    We finally got to try out this place! It was quite hidden, but I loved the feel of privacy when you're hanging out here. I tried the recommended Spicy Tuna pasta & loved it too.

    Great place to work around the Old Manila area! Ordered their Berg's coffee, and was surprised at how big the glass I got was. Caffeine kick was also superb.

    Great for a change of scenery from work from home setups. Good food and coffee! Chic ambiance.

    They also support local artisans to display their craft at their cafe. The staff are friendly, like really friendly. You will always have something nice to deposit in your memory bank whenever you visit this place.

    Finally, a place with great coffee and beautiful people in the heart of Manila.

    I love the vibe and the coffee. I love the ambiance, finally a coffeeshop in downtown manila that doesn't scream "franchise" Thank you for supporting Escolta!

    When I heard the story of a coffee shop in Escolta—that it has come of age (yes, a cafe has found itself), it made me feel wistful. It’s weird. I never knew I could relate to an establishment (well, technically, it’s not just the literal coffee shop, of course) when it says, “It knows itself better.”

    Shipping & Delivery

    Orders ship out via the following methods: 

    • Same Day Delivery
    • Via Courier (3 Working Days Metro Manila • 5-7 Provincial)
    • Store Pickup

    Learn More

    Great Philippine Coffee

    We proudly highlight and use great Philippine coffee processed by Kalsada Coffee!

    Kalsada champions Philippine specialty coffee. Their priority is to support Filipino coffee producers and their dedicated efforts to bring quality coffee to the market.

    Check out Kalsada

    Quality & Freshness

    We take great pride in the quality of our fresh food, coffee, and packaged goods, so we guarantee your satisfaction with every product, every time.

    Shoots & Events

    We rent out our space for commercial shoots, film shoots, pre-nup / pre-debut shoots, seminars, and events with very reasonable rates.

    Inquire Now