With the increasing complexity of public security, criminal methods are becoming more covert and professional. In solving cases, the detection of tiny spaces such as keyholes has become a crucial link. Shenzhen Vsndt Co.,Ltd's brand "VSNDT" industrial endoscope, with its unique advantages, successfully provided a high-precision industrial endoscope system to the forensic department of a public security bureau for the detection of keyholes and other tiny spaces.