Fantastic funnel!
Works great for holding shake contents on the go. I've flown cross-country three times now in the last month with them in my checked and carry-on bags and found no leakage or caps unscrewed upon arrival. These funnels also hold PLENTY of powder (I mix two scoops of collagen + two scoops of Level-1, and sometimes a half scoop of Ignition as well) and won't leave you bringing baggies along for whatever extras you want to add into your shakes.