This bill exempts certain less-than-lethal projectile devices from federal firearms taxes and regulations under the National Firearms Act. The legislation creates a new category for devices that cannot fire standard ammunition or projectiles exceeding 500 feet per second, are designed to avoid causing death or serious injury, and cannot accept typical firearm magazines. Manufacturers can request determinations from the Treasury Secretary within 90 days about whether their devices qualify for the exemption. The Treasury Secretary must maintain and annually update public lists of qualifying devices and report to Congress on emerging technologies in this space. The bill takes effect immediately upon enactment for new sales, with a 180-day grace period for initial manufacturer requests for device classifications.