The Matrix Algebra Tutor: Linear Algebra

Because you never know. Be prepared for anything with this analog-digital Diesel watch's ability to track four different times. Stainless steel bracelet and round case, 60x20mm. Black patterned dial features three analog subdials, one negative display digital dial, date window, white stick indices, silver tone screws, luminous hands and logo. Quartz movement. Water resistant to 50 meters. Two-year limited warranty.

Fierce styling lurks in the shadows with this sleek Montreal watch from Lacoste.