Personalized Mechanic Nuts and Bolts Youth T-Shirt. Mechanic Nuts and Bolts Youth T-Shirt - White, with "mechanic" underlined with a wrench and bedecked in nuts and bolts, are a unique gift design for professional and weekend mechanics! Let the good times roll in a durable T-Shirt that takes kids from school to play in an amazing array of colors. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar.