Security Class 15 RU indicates the level of a safe's resistance against forced entry. The value is expressed in RU units, where RU stands for "Resistance Unit". This number is not a simple time value in minutes, but the result of laboratory tests conducted according to precisely defined standards. During these tests, technicians attempt to open the safe using various tools, from crowbars to drills. The resulting RU value is calculated based on the tools used and the time required for partial or complete penetration. Generally, the higher the RU number, the more secure the safe. A value of 15 RU represents a basic level of protection, suitable for storing low-value items. Insurance companies use this classification to determine the maximum amount for which the contents of the safe can be insured.
