Replacement battery for 3850.000.020.000. Specifications: 2600mAh, 6V, Alkaline. Compatible with: 3850.000.020.000, Safe-O-Pin Pincode, Coin Operate Lock. Replaces: SAFE-O-KIEFER 3850.000.020.000. SAFE-O-KIEFER replacement battery designed for Door Lock devices. Tested for reliability and long service life.