Komelon Self Lock Speed Mark Tape Measure. Revolutionary Komelon tape measure functions like they always should have. With Komelon’s Self-Lock tape measures, all you have to do is pull the blade out, let it go and the blade stays out. To safely retract the blade, press the top button and control the speed of return. This 16′ x 1″ Self-Lock Speed Mark has a nylon coated blade with fractional graduations for easy read and accurate measurement. Komelon’s yellow Self-Lock case is ergonomically designed for user comfort. Once you try the Self-Lock you may never use another. Self locking blade with thumb push button return. SpeedMark fractional graduations on blade. ABS case with protective rubber.