We use these bottles. They are very well made and well designed and we highly recommend them.
Here is what Avex says about the bottles:
The Brazos 24/25 oz. water bottle is spill and leak proof with its one-touch AUTOSEAL technology. It features a spout shield for protection from dirt, as well as a clip-on handle making it convenient for attaching to backpacks and gear. Made with BPA free plastic. Includes a Lifetime Guarantee against manufacturing defects.