I recently returned to rebuy the ice blue bottle as a backup. I have two of these in constant use, one for cold green tea, one for water. These bottles are reliably tight and very sturdy. I had one drop to the kitchen floor several times (out of a backpack side pocket when bending to the floor). No damage beyond some light scratches in the paint! Cold drinks keep cold all day long, but I haven't timed how long hot drinks keep hot. In any case, I would come back for those double-walled steel bottles again! They're great!
Great experience with AKAZUKI.
The product arrived as described, well packaged, and on time.
Very satisfied with the quality and overall service.
Would definitely order again.