Doona vs. Evenflo Shyft DualRide: Battle of the Car Seat Stroller Combos The Car Seat Pros Customizing Your Uppa Baby Stroller in Boston Hub GLP 1 V2 Regenics Evenflo Balance Part 4. The easiest way to open this vent is to squeeze it between your thumbs. This needs to be done before using it the first time. It is also worth checking periodically, especially Modes Nest Travel System Graco Baby Gym Bench Used Hammer Strength Adjustable Bench Cybex ST MAB Adjustable Bench USED