USB interface, universal for laptops, PCs or computers, not suitable for USB 3.0. 4-digit password combination, easy to set. Easy to install and use for high security of computer equipment, anti-theft. Works with all, desktops, docking stations with built-in standard security lock hole. Instructions: Align the password with on the lock body and turn the code switch in the direction of by hand and hold it down until the step is completed (you must not release during the setting process). Set the first password, for example 1-0-0-0, release the key switch, check if the password has been set correctly, then repeat the steps above and then set the second, third and fourth passwords respectively. After setting the password, you must immediately dial the password to prevent distorted characters caused by accidental misuse of the code switch. Check that the password is set and then lock it to your computer. Specifications: Type: USB Laptop Lock Used for: Most digital devices with USB hole Features: Universal, 4-digit password, Easy to use, Laptop Security Cable length: 1.9m Cable diameter: 5mm () Material: alloy color: black gray + silver Package contents: 2 x Lock chain cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The allowed measurement error is +/- 1-3 cm.