A student of Zhongyuan University of Technology, who frequently fogets to bring his key, makes fingerprint lock with roommate for their dorm room in Zhengzhou, Central China's Henan Province. Photo: Screenshot of Pear Video

A student from a Central China university, who frequently forgot his dorm room key, solved the problem with the help of a roommate by inventing their own low-cost fingerprint lock.

Students surnamed Sun and Zhang from the Zhongyuan University of Technology in Zhengzhou, Henan Province made a fingerprint lock for just over 100 yuan ($14.50), Pear Video reported on Sunday. Fingerprint locks usually retail for as much as 3,000 yuan. 

The two students bought a fingerprint detector and other materials online and assembled the parts on their own. The fingerprint lock took the two students a month to design and install, and it works perfectly.

Sun and Zhang are keeping the traditional lock close at hand just in case the fingerprint lock stops recognizing their digits or perhaps starts admitting others. 

Sun and Zhang's other roommate told Pear Video that he feels proud and privileged whenever he puts his finger on the sensor. "Students from other dorm rooms 'wow' me all the time," he said. 

Pear Video