The flexible gasket that seals a car window acts as a cushion when trying to enter the vehicle with a baton. Window punches require straight-on activation placing an officer in front of a threat. They can carry the hand through a window and into the interior of a vehicle. Most window entry tools are not readily available. They are in the patrol car or equipment case at the split second when they are needed. The ASP BreakAway® subcap is designed to be interposed between the cap and handle of an ASP expandable baton. It is always available. It is readily at hand. Removing the baton cap exposes the three ceramic pins of the BreakAway. Set in a machined aluminum geodome, at least one pin will make contact with the tempered glass of a car window whatever the angle of application. The officer can stand to the side of a threat, grasp the tip of the baton and easily shatter any vehicle window. Entry is rapid and tactically sound.