Source: http://feedproxy.google.com/~r/yankodesign/~3/a3pMJJQEvkQ/
No more approximations, not even if you're blind. A reassuring sound of "Tikk, tikk… tekk", two fingers and some Braille embossed cylinders, mix them up and you got yourself the Tikk-Tekk Rainbow! It's a low-cost universal measuring tool that uses a string (ranging from 1cm to 100 cm) wrapped within the casing, and is extended between the finger tips. Kinda like how you use your hands to gesture an estimated distance; only Tikk-Tekk gives you the exact numbers.
Designers: Guopeng Liang & Yun Li