Primary Arms 2 MOA Advanced Micro Red Dot (MD-ADS) Riflescope (Angled Front Lens), Black 2 MOA RED DOT: The ultra-sharp 2 MOA dot is powered by a single CR2032 battery BATTERY LIFE:Features up to 50,000 hours of battery life from the included CR2032 battery. RUGGED AND DURABLE:Constructed of aluminum with a hard-coat anodized finish and is waterproof. If a defect due to materials,workmanship, or normal wear and tear has caused your product to malfunction,Primary Arms will either repair or replace.