Hi Cathy, Thanks for your message. The sleeve has also time on it. To monitor how much water you consume in a specific span of time, you need to remove it. The sleeve serves as an additional protection for your bottle. Our customers are everything to us at Bevgo and we want to make sure all of our customers are 100% happy so If there is anything further we can assist you on please let us know. Thanks, Romina Bevgo Customer Care
You can not tell exactly how much water you drank with the insulation sleeve on. I usually just estimate. There are no markings after 5pm because I assume the by then you have drank your daily requirement.