The World's Strongest Steering Wheel Security Device!The Disklok steering wheel device is truly a one-of-a-kind design for vehicle security. With over 20 years of history and thousands of satisfied customers, Disklok remains the undisputed strongest security device available on the market. Period.Even the most daring and determined car thief does not stand a chance against Disklok's multi-award-winning design that has protected countless vehicles across the United States, United Kingdom, and Europe.Disklok's ability to spin on the steering wheel when attacked represents a unique advantage over the lock-in-place competition. This patented feature prevents active steering and damage to the OEM ignition lock cylinder while the Disklok is engaged.Disklok also boasts product accreditation and approval from Thatcham – a highly respected, independent UK laboratory along with SKB-IKOB in Europe passing their own stringent testing criteria.Choosing the Right SizeDue to its intuitive design, the Disklok can fit and protect over 99% of cars and light commercial vehicles on the road today. The Disklok is available in three sizes, so make sure to select the model with a sizing range that best fits your individual steering wheel. To find out what Disklok you need just measure the outside diameter of the steering wheel. Measuring your steering wheel left to right will give you the required size in inches. Small size | 13.7 - 15.3 inchesMedium size | 15.4 - 16.3 inchesLarge size | 16.4 - 17.3 inchesThe Disklok is supplied with three keys, in case one or more are misplaced. It is always advisable for extra security to separate your Disklok key from your car keys. In a situation whereby your car keys are stolen, thieves would not also have access to open the Disklok device in use.Keeping a note of the tag number safe is also very important, as this number is required to obtain replacement or duplicate keys. Manufacturer DiskLok upc 5035895159286 Weight 11.000000 Length 16 Height 4 Width 16