Time to breathe new life into your Blackwing- to enjoy Blackwing to the last - Bring new life to your blackwing pencil that has been shorter, and prolong its life is the Blackwing Pencil Extender. The design is very simple. Just plug it into the hardware. Works with all models of blackwing pencils. The body is machined from aluminum and the tip is made of hard rubber for a snug fit.