Depending on the model and the execution the rulers have red imprinted tens depicted on the measuring scales, a recto-verso scale (reverse scale) and/ or fixed metal ends. Some models were conceptualized for a particular purpose such as the LongLife® Electro meter. This one is specifically made for an electrician. What makes it stand out is its integrated pull-in aid buildt in the first link. It has additional markings for easily measuring the distance between electrical sockets. It is also sample tested and verified for withstanding electrical currents of up to 1000 volt.
One particular folding ruler differs from the rest of our LongLife® meters: the LongLife® Plus Composite. The basic material is the same, however, it is enhanced with glas fibers on both sides. This makes it much stronger and acurate, bringin it up to an accuracy class of II.