How long does it keep drinks hot or cold?

The listing claims insulated stainless steel construction but gives no tested hold times. Treat any hot or cold performance as unverified until independent tests or owner reports appear.

Is it really leak-proof?

It is marketed as leak-proof with an easy-clean lid. No owner reports confirm this, so test it over a sink before trusting it in a bag with a laptop.

Does it fit in a car cup holder?

At 500ml/18oz it is a mid-size bottle, and the slim cylindrical shape should fit most standard cup holders. The listing gives no base diameter, so check before buying if your holder is narrow.

Can I put it in the dishwasher?

The lid is described as easy-clean, but the listing does not state dishwasher safety for the body or lid. Hand washing is the safer choice for insulated steel.

The bottle with its lid. No straw, brush or spare seal is mentioned.

How does it compare with a Hydro Flask or Yeti?

Those brands have published insulation tests, wide accessory ecosystems and long warranties. The Kyusrd offers the same basic double-wall steel idea without that proof or support.