The space between the vertical slats is approximately 2 inches.
This is NOT made for adults to hang on or lean on. It WILL support the weight of a toddler/young child (25-40 lbs.) trying to climb over it. If it is properly attached to the wall, the gate will last for years. Unfortunately, the plastic parts that latch and unlatch the gate itself will eventually fail. Other wise, it is sturdy, but this is a design flaw that the manufacturer should correct.
Hello Wansman! Thank you for your recent inquiry with The Home Depot. For replacement parts, please reach out to the manufacturer, Munchkin, at 800-344-2229. We appreciate your business and look forward to serving you in the future. Thank you for shopping Home Depot.