SureFire Writing Pen Black Click Tailcap MechanismWrite With The Right Instrument. The sleek SureFire Pen IV is precision machined from high strength aerospace aluminum and hard anodized with a rugged Mil Spec finish in black. It features attractive stainless steel hardwarethe pocket clip, nose cone, and retractor buttonthats as tough and durable as it is attractive. Inside every Pen IV is an imported Schmidt easyFLOW 9000 ballpoint pen cartridge for smooth, effortless writing. Like all SureFire