Slotted screwdrivers, which are also known as the flat head screwdriver, flat blade screwdriver, or straight screwdrivers, are the oldest forms of screwdrivers.they are used on screws with a simple slot spanning the width of the screw, also called a slotted screw. Clutch head screwdriver the clutch screwdriver begins with higher torque and can resist greater turning force. Screwdrivers and Nutdrivers 42255 Artesia Tool 2 Piece 20 So before you begin, just make sure the screwdriver fits the screw head properly. What is a slot screwdriver . Flat head (slotted) screwdriver types are different, measured by fractions of an inch. It’s the oldest and most common screwdriver in the world. The slot has parallel walls, you will have a much better fit if your screwdriver tip had too (no taper) and was sized correctly for the screw slot (in width and thickness) that is why in woodworking, your best bet are a set of parallel tip screwdrivers. It is easy to get off center. Thankfully, t...