D-ring Lock 7.5ft, 8mm thick OD braided steel cable or armor link Cobra Cable Weight: Material: Color: Silver Patent No. 5133203 on push lock USA: USD564338 Taiwan: D119034   Feature Specialized lock design for all desktop tower computers with a D-ring locking device Universally lockable on all hp desktop chassis Work with other accessories to lock multiple devices Very easy to use, just a push Master Key or Grand Key available