How many times have you found yourself having a ruler and without a writing instrument to draw, or vice versa? Whether not if have this unfortunate experience, it does not matter. What matters is, there is a tool that will not leave you in such predicament.

TA+d One 3 Ruler with Integrated Pe
Meet the TA+d One 3, an aerospace-grade aluminum scale ruler with Pilot FriXion erasable pen neatly integrated into it. The scale ruler has a magnetic feature that allows the companion pen to align perfectly into the sleeve/ruler and stay where it should until it is ready to be used.

The triangular cross-section ruler also features rubber protected tips that allow you to carry out contactless interaction such as when punching numbers at an ATM. The rubber ends also double as handy erasers for, well, easing.