The Rivers STEM is a 500 ml stainless steel vacuum flask designed for daily commutes and outdoor use, keeping beverages hot for up to 6 hours at 73°C / 163°F or cold for up to 6 hours at 7°C / 44.6°F. It is available in three colors (Ash Blue, Sandstone, and Black) and in two configurations: a standard model and a Bottle Leash model with an attached carrying strap.
The STEM flask's stainless steel body is vacuum-insulated to hold temperature across a full six-hour window, whether that's a morning of back-to-back meetings or a half-day hike. At 230 g / 8.11 oz and 225 mm tall, it sits in a standard bag side pocket without adding meaningful weight to a daily carry.
The interior is electropolished to create a smooth, gleaming surface that resists odor buildup and makes residue easier to rinse away. The lid and plug use polypropylene and silicone rubber to form a spill-proof seal, so the flask can ride in a bag without a protective sleeve or secondary bag.
The Bottle Leash configuration adds a polypropylene hook-and-Velcro strap that clips to a pack or serves as a carry handle. The leash is integrated into the Bottle Leash model's design and cannot be added to a standard STEM after purchase. Choose the configuration at the time of ordering.
| Specification | Detail |
|---|---|
| Capacity | 500 ml / 16.9 oz |
| Dimensions | W 80 mm x D 70 mm x H 225 mm (W 3.14" x D 2.75" x H 8.85") |
| Weight | 230 g / 8.11 oz |
| Hot insulation | 73°C / 163°F for 6 hours |
| Cold insulation | 7°C / 44.6°F for 6 hours |
| Body material | Stainless steel (electropolished interior) |
| Lid and plug materials | Polypropylene, silicone rubber |
| Ring material | Stainless steel |
| Leash and hook materials | Polypropylene, polyester (Velcro and tag), Bottle Leash model only |
| Colors available | Ash Blue, Sandstone, Black |
| Not suitable for | Microwave, dishwasher, dryer; keep away from direct flame and heat sources |
| Origin | Designed in Japan, made in China |
The Rivers STEM suits commuters, hikers, and anyone who wants a compact, spill-resistant flask for hot or cold drinks across a half-day outing. The Bottle Leash model is a good fit for those who carry a backpack and want the flask accessible without opening a pocket.
The STEM holds 500 ml, which is not suited to situations requiring larger-volume hydration. It is not dishwasher-safe, microwave-safe, or dryer-safe, and should not be used near direct flame or heat sources. The Bottle Leash is built into the Bottle Leash model only; the two configurations are not interchangeable.
The Rivers STEM vacuum flask maintains hot beverages at 73°C / 163°F for up to 6 hours and cold beverages at 7°C / 44.6°F for up to 6 hours under standard conditions.
The Rivers STEM holds 500 ml / 16.9 oz, making it a single-serving flask suited to a commute or a half-day outdoor activity.
The Bottle Leash model includes an integrated polypropylene hook-and-Velcro strap for clipping the flask to a bag or carrying it by hand. The standard model does not include this strap, and the leash cannot be added to a standard STEM after purchase.
The Rivers STEM is not suitable for the dishwasher, microwave, or dryer. Hand washing with water and soap, followed by air-drying or wiping dry, is recommended. The flask should also be kept away from direct flame and heat sources such as gas stoves and ovens.
The Rivers STEM's electropolished stainless steel interior resists odor and residue buildup. Hand wash with water and soap, then air-dry or wipe dry. Do not use abrasive cleaners, and do not place in a dishwasher or dryer.
At CoffeeRoast Co., we are passionate about coffee. Every piece from our catalog is designed and rigorously tested to make sure you get perfect and consistent roasts every time.
We’ve partnered with various manufacturers that operate around the globe under a strict set of guidelines both on a local and corporate level so that when you shop with us, you will be able to select from the highest quality coffee roasters and coffee equipment available on the market.
Whether you are a coffee enthusiast or a small business owner, you're sure to find whatever so you have the perfect roast you've been looking for.
Any questions or concerns? Please call us at (312)-298-9262 or email us at support@coffeeroastco.com and a member of our professional support team will be in touch with you as soon as possible.
CoffeeRoast Co. will ship orders as soon as possible in the order they are received. If you purchase multiple items, they will be shipped to you based on lead time and availability. This way you get as much of your order as soon as possible, which means that your order may come in separate packages, especially if you order products from different brands.
We will pay shipping for products returned due to product defect, misrepresentation, or false description. Afterward, we will initiate a full reimbursement should you decline an offer to replace the item with the same item of equal value and assured quality.
Order Confirmation:
As soon as you place your order with CoffeeRoast Co. you will receive an order confirmation e-mail. This means that your order has been logged in our system and your credit card has been pre-authorized for the purchase. We then work with our partners to confirm and prepare your order for shipment. If any item you order is on backorder or unavailable for whatever reason, we will cancel the credit card authorization and duly inform you via e-mail.
Order Shipment:
Orders are shipped within five business days from the date you place your order unless specified otherwise on the product page. The product page will contain the most accurate estimate on shipping and lead times. Shipping and lead times provided on the product page are our best estimates based various factors including order volume, information from our partners, shipping issues, etc., and may vary due to these factors.
You will receive an email containing the tracking information of your order after the order has been shipped to your location. If you do not receive tracking information from us within seven business days of the lead time specified on the product page, feel free to follow up with us at support@coffeeroastco.com.
Damages:
We will take full responsibility for any obvious damage to your product caused by packaging or delivery of an already defective product. Please carefully inspect the packaging of your item(s) when they arrive, if you notice any damage or defects, you should document them when signing for delivery. If the item(s) contained in the package arrives damaged, please send photos to support@coffeeroastco.com, and we will process an insurance claim on your behalf.
Returns and Cancellation Policy:
We back all our products with a customer satisfaction guarantee, so we've created a fair return and cancellation policy.
In most cases, once the order is processed, it is final and not cancellable due to the larger nature of these products. Requests for returns/exchanges after the item has been delivered will be evaluated on a case by case basis. Any return request is subject to an administrative and cancellation fee equal to 10% of your order with a minimum of $35.
Before returning any product, you MUST obtain a return authorization from a Coffee Roast Co. customer service representative. We can only process AUTHORIZED returns for items.
To make a Return or Exchanges:
Return or exchanges request submission must be within 14 calendar days upon receipt of shipment unless noted otherwise on the product description page. Your return must be in original packaging and unused.
We encourage using USPS flat-rate shipping in returning products to receive a shipping expense refund. Buyers must ensure all returned parcels delivery receipt AND signature confirmation. We highly recommend insuring your parcel as we cannot issue a refund for an item that we do not receive back should it get lost/damaged during transit.
Refunds:
Should an item be returned because it was defective, misrepresented, not as described, etc., CoffeeRoast Co. will issue a full refund and will reimburse the customer for all shipping expenses associated with the return.
Please allow 5-10 business days from the time the returned item is received to process a refund. Refunds will only be issued to the original form of payment that you used when placing your order.
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At CoffeeRoast Co., we ensure that you get the absolute best prices for coffee roasters, all while ensuring the highest quality. As always, high-quality roasters do not come cheap, but we ensure that they are reasonably priced using our exclusive contracts with the best coffee roaster manufacturers.
We want you to be able to make your purchase with us in confidence. Putting our money where our mouth is, we offer you a price guarantee on all orders. If you find out within six months from your purchase of an item from CoffeeRoast Co. was offered at a lower price than us from the time of purchase, we will refund the difference.
To get a refund, all you need to do is e-mail us a link to the product on our website and the same product on our competitor’s website within six months from the date of your purchase, and we will process the refund accordingly.
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