I'd suggest looking for a holster system that is concealed.
If the average person looked through your truck window and saw an empty holster system, they wouldn't know what they were looking at. However, it's a huge advertisement to criminals that there's a good chance there is one or more guns in your vehicle for an easy smash and grab.
Maybe I'm just paranoid, but I do my best to hide my guns in my truck. I keep one of my EDC pistols in my laptop backpack. It sits in the passenger floorboard positioned for easy access. I appendix carry my smaller EDC pistol all the time, so it's relatively easy access at all times even when I'm driving. I realize not everyone has my setup, but I wanted to share how I store my guns in my vehicle.
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