Vision windows are available to meet ballistic threats from UL Level 1 (9mmHandgun) to UL Level 8 (7.62mm Rifle), .50 caliber and beyond. Vision windows can be provided as fixed or side-hung casement units with frames constructed of steel, stainless steel or bullet resistant aluminum. Units can be designed for individual openings or joined together for larger, multi-lite openings. Several window configurations and protection levels are UL Listed. Please consult NABP for details.