JumboMax makes oversized golf grips, and that single sentence undersells how much category the brand has carved out for itself. Founded in 2009 by John Mazzanoble and headquartered in Lake Park, Florida, the company spent five years in development before launch, building a super-oversized grip stable enough for tour play, durable enough to outlast a season, and ergonomically sized to the human hand rather than the 500-year-old standard inherited from a Scotsman wrapping sheepskin around a hickory stick. The premise was simple. Squeezing the club is the universal sin every instructor identifies. A bigger grip means more surface contact, less squeeze, faster clubhead speed, and more consistent face control. The product backed up the pitch. The category-defining moment came when Bryson DeChambeau started gaming JumboMax grips on the PGA Tour. Bryson is the most public face of the brand, but JumboMax now sells across multiple swing-grip lines including the Wrap Series, Tour Series, UltraLite, and STR8 Tech, plus a putter line that includes the JumboFlat 17, ArmLock 21, and Mid Jumbo. The JMX Zen Lite and JMX UltraLite swing grips are 10 to 25 percent lighter than skinny grips, which is part of the pitch: bigger and lighter, not bigger and heavier. JumboMax leans hard into the fitting layer. The brand built an iOS Intelligent Grip Fitting App that uses TrueDepth camera technology to capture 21 data points from a golfer’s hand, then runs them through a tour-tested algorithm to recommend a size. There’s also an online fitting tool for non-iOS users. Annual revenue sits around $5.4 million, which is small in golf-equipment terms but meaningful for a single-product-category brand competing against Golf Pride, Lamkin, and SuperStroke. The audience is players who have tried skinny grips for decades and are open to the idea that the standard size was always wrong.