I bought several of these as the paved trail I ride on still has enough grime on it that an uncovered bottle spout attracts more dirt than I want to drink. The insulation is also very effective. If filled with ice water or iced hydration mix, the contents stays cold for about 3 hours even on 90+ degree days and bright sun. The only downside is that the capacity is just a bit over 16 ounces - so I carry 2 on hot days. I've tried other "dirt series" type bottles and they still collect grime on the mouthpiece. These are relatively expensive but work well, especially if you want to drink without swallowing some trail dirt.