What is the difference between tilt lock and tilt tension on an office chair?

Tilt tension (a knob under the seat) adjusts the resistance required to recline. Tilt lock is a separate lever that locks the chair at a specific position. Use tilt lock for forward-leaning concentrated work; leave it unlocked for extended reading or screen work. FindOfficeFurniture.com chair specs note tilt mechanism features — call 888-719-4960.