The Cap-O-Matic line utilises cap activation to extend and retract the point, and each carries a gas pressurised PR style ink refill cartridge, which means that they feature all of the unique capabilities that are synonymous with Fisher products: they will write upside down, at any angle, under water, through grease, in extreme temperatures (-30 to +250 degrees F), on almost any surface, three times longer than the average pen, and, of course, in the gravity-free vacuum of Space.