It's a battery - that's also a car key! Embrace the fusion of stealth and functionality with the Car Key Penjamin by Smyle™ Labs. With its patented design that mirrors a real car key, this cartridge car key penjamin elevates your experience to new realms of convenience and discretion. Fits most standard .5g and 1g carts (not included). Made with high-quality materials and built to last.