This is an AJC Brand Replacement for a Park Medical Electronics Lab 811AL 811B 811BTS 811L Doppler 12V 1.3Ah Medical Battery Voltage: 12V (12 Volts) Capacity: 1.3Ah Terminals: F1 Battery is compatible with these Brands: Park Medical Electronics Lab. IMPORTANT: You MUST RE-USE: your existing cabling and hardware. These are replacement batteries only. NOTE: It is your responsibility to verify the batteries being ordered match the batteries in your unit prior to placing your order. We are not responsible for incorrect orders. Chemistry: Sealed Lead Acid (AGM). DISCLAIMER: Our products are not affiliated with, authorized by, created or sold by Park Medical Electronics Lab.