Olight S1 Baton Cree Xm-l2 Cw 500 Lumen EDC LED Flashlight With Skyben Holster The S1 is the smallest side switch LED flashlight ever produced by Olight. The S1 is powered by 1 x CR123A to maintain the compact form factor.Note:Battery is not included in the package. S1 original battery is available to purchase at ASIN: B00YRX8PEY The S1 has a low profile side switch that is designed to prevent accidental operation. The light also features a pocket clip, a lanyard hole, and the signature magnetic tail cap.