It's a plastic bottle. Mine is red. I've seen yellow ones too. Pretty durable. Makes a nice sound when bottle is full.
Mimics smells of the substances it contains regardless of washings. You might put tea in it, and it will eventually smell like a tea shop. If you put coffee in it, it will eventually smell like burnt tobacco. Beans will ultimately smell like farts. Also, the lid does not connect to the bottle. I tend to lose lids more than anyone I know. Does not make a good hammer either.
It's just a bottle. There are more/less expensive/cheap alternatives. It's all about the FEEL. How does it make YOU feel? Regarding the hammer comment, a real hammer works better than this bottle.