Features:1. High quality alloy lock case, the overall lock case is a high quality alloy, which is waterproof.2. After special cold rail processing, hard casting.3. The is chrome-plated, with exquisite craftsmanship and durability.4. More effective against violent damage.5. Suitable for indoor and outdoor doors.Specification:Product model: 38DPanel material: zinc alloyPassword length: 2-4 digitsApplicable door thickness: 10-60mmApplicable type: indoor, outdoor doorFeatures: waterproof, no batteryCenter distance of the lock tongue: standard 60mmLock Size: about 107 * 43 * 20mm / 4.2 * 1.7 * 0.8inPackage list:1 * Mechanical lock set1 * English manual2 * Installation packageNote:The passwords are not in order, the numbers cannot be repeated, refer to the manual.Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.Change the Password:1. Remove the 4 red screws from the rear panel of the outer door keyboard.2. Open the back panel and be careful not to tamper with many small parts inside.3. See 3 red ciphers, 6 blue regulars and 1 C.4. Press the C button to move the internal lock piece, but do not move the C piece.6. Pay attention to the different characteristics of the red and blue locking tabs and insert them into the slots.7. After placing it, cover the back panel after correcting it. After tightening, check it repeatedly. Edit the password button according to your own, and you can unlock it smoothly and confirm the success.8. Please pay attention to that there are spare locks in the accessories, you can change the number of passwords to 2 to 4.