Your PADI Tec Instructor will explain the equipment you'll use and go over basic tec diving procedures, such as the importance of diving in teams. You'll get in the water, make gear adjustments, then simply explore and get a feel for the equipment.
Discover Tec may credit toward the Tec 40 course if you successfully complete the Tec 40 Training Dive One required skills. Ask your instructor about this option if you're interested.
You'll want to have your mask, fins and exposure suit. Your PADI Tec Instructor will have the technical diving equipment, including but not limited to two tanks, primary and backup regulators, and technical diving BCD and harness or sidemount harness.