The collapsible fabric design is what sold me — it folds down flat enough to shove in a jacket pocket, then pops open for water stops. My lab drinks from it without half the water ending up on the trail.
Sophia C.★★★★★
Tossed this in my daypack for a 6-mile hike and it clipped flat against the back, barely took up space. At the summit I popped it open and my lab drank a full bowl without it tipping over. Folding it back down was just as quick.
Samuel★★★★☆
Tossed this in my daypack for a hike and it flattened down flat enough to forget about. The fabric holds water fine but gets a little damp on the outside after a while, so I just set it on a rock.