Shipping added another 10 dollars that I wasn't expecting. For that price I would have expected faster delivery. Items didn't fit inside shipping box, they were poking out of the top. I use the hiit bottle every day and it functions as intended, but there is room for improvement. The lid is too difficult to unscrew, so it probably needs deeper, more numerous grooves to grip. The tea infuser should be on the bottom of the bottle so it contains to infuse as you drink or you can have only a little tea if you want. You can't use infuser for tea unless bottle is full, in other words. I'm using a drop in tea infuser ball instead, it functions a protein shaker too. If your tea infuser could be detached and dropped down into the bottle it would be great. The top of the lid is taller than necessary and I don't know the purpose of that shape. There is already a place for a lanyard so why another hole in top. At least fill the lid with insulation if it's going to be big like that

Really enjoying my HIIT bottle. Keeps my protein shake cold. The only thing is that sometimes the lid is a little hard to unscrew. One thing that could improve is customer service and supply. It took a really long time for me to get my bottle, and I wanted to order the tumbler lid and straw, but it has been out of stock forever! Too bad.

Overall the bottle works well, but could use improvement. There are no ounce measuring marks in the bottle. The cord that can be used on it smells awful if it gets wet. However the biggest issue is the cap. If you wash the bottle including cap then reuse the bottle, water gets trapped in the cap and leaks out. You have to shake it all out and air dry.

This is my 3rd bottle, v3.0 bottles keep getting better and better! Very durable

Improved design over other options available HIIT is more functional and easier to clean - typically used 4 days a week while remaining stoked with results... "Chicks dig it" (grin:)