A technical patent diagram for a golf club is rendered in white line art against a charcoal black chalkboard background, showing detailed cross-sections and measurements across five labeled figures. The composition balances scientific precision with the worn, authentic texture of vintage patent documentation, evoking early-twentieth-century industrial illustration. Built from double-wall stainless steel and made to order, holding 20 ounces with a snap-on lid, a standard-cup-holder fit, and wraparound artwork. Your commute carrying original art instead of another branded tumbler.