Overview The Klein Tools 33803 ProFlex kit combines a comprehensive 42‑bit collection with an adjustable screwdriver, all housed in a rugged, MODbox‑compatible case. Crafted with high‑impact rated S2 steel, the bits feature a tuned torsion zone designed to absorb impact energy and help extend tool life. The modular case system, steel hinges, and stay‑shut latch are built to endure busy job sites while keeping contents protected and organized. Built for durability and precision IMPACT-REINFORCED DESIGN: 42 bits plus an adjustable screwdriver, ready for repetitive use in demanding environments. TORSION ZONE TECHNOLOGY: A recoil‑dissipating zone helps reduce wear on bits during high‑torque tasks. CUSHION-GRIP HANDLE: Ergonomic, soft‑touch grip with a quick‑adjust push button for easier length changes and comfortable handling. MAGNETIC BIT HOLDER: Strong magnet inside the barrel helps retain bits and securely hold fasteners as you work. MODBOX ACCESSORY CASE: Compatible with other MODbox designs for stacked storage and easy transport. STORAGE TRAY: Keeps loose fasteners and extra bits neatly separated for quick access. Smart storage and on‑site organization MODBOX COMPATIBILITY: Stackable design makes it simple to pair with similar organizers on a workbench or in a tool cart. RUGGED CONSTRUCTION: Steel hinges and a stay‑shut latch help protect contents when the kit travels between sites. ORGANIZED SETUP: The compact modular system reduces clutter and helps you locate the right bit faster. Real‑world use cases Designed for professional tradespeople and serious DIY enthusiasts, this set supports a range of tasks—from assembly and repair to routine fastener changes. The magnetic holder helps keep small screws handy, while the adjustable screwdriver speeds up variable-length work. The case’s modular design makes it easy to expand with other organizers as your toolkit grows. About Klein Tools With a heritage spanning more than 160 years, Klein Tools delivers premium, professional‑grade hand tools. The family‑owned company emphasizes quality materials, precise workmanship, and tools designed to stand up to daily use on the job site. What you get 42 impact‑rated bits Adjustable screwdriver Impact‑resistant MODbox case with storage tray Modular design compatible with other MODbox cases FAQ Q: What is included in the Klein Tools 33803 ProFlex set? A: The kit includes 42 bits and an adjustable screwdriver, totaling 44 pieces, stored in an impact-resistant MODbox case. Q: Is this set MODbox-compatible? A: Yes, the case stacks with other MODbox designs for organized tool storage.