Tactile Turn Ultem Bolt Action Pen in black, Short 5.1" (10-BA2-ULT-BLA). Official listing is Ultem 1000 body material with a titanium mechanism and a stainless steel clip. Official page lists the material as chemical resistant and flame retardant. Official specs: 0.485" diameter, 5.1" long, 0.70 oz, Schmidt EasyFlow 9000 refill. Designed, machined, and assembled in Dallas, TX. Specs from the tactileturn.com Ultem Bolt Action Pen page.
Black Ultem Short. Light 0.70 oz body. Parker-style refill.