This video shows what you can fit inside Spirit's 18x14x8 bin as your free personal item. UPDATE: Speaking generally, Spirit may not make you measure your bag at the gate. If you bag looks like it would fit, they usually let you pass. Allow this video to be a reference to what will absolutely fit in their bin, and then the choice is yours as to how much bigger of a bag you'd like to try to get on a Spirit plane.
Views: 7460 Jason McCullough
Here’s the description from Amazon of this pack: Trekking King Tactical Backpack Military Outdoor 3-day Assault Pack 60L Survival Rucksack 1000D Army Molle Bug Out Bag Perfect for Hiking Trekking Travelling and Hunting Here’s the link for it, but I cannot guarantee it will work after enough time has passed since this video. https://www.amazon.com/dp/B0745GN1TL/ref=cm_sw_r_cp_api_i_XedeBbJYYJT0J
Views: 5957 Jason McCullough