I take pictures at the time back a lot of old analog cameras without built-in Beli. Since you can not always estimate the correct exposure time-aperture combination / wants, needed a handheld exposure meter. And for the Twin Mate is ideal. So small it fits in your pocket, easy to use and also visually it fits perfectly with my old cameras. I love this small little device and can recommend it without hesitation. One perhaps should not let him fall, because it consists entirely of plastic, but that one should not do so with other devices. In addition, you can at the price also do not expect the highest quality materials. Nevertheless, there's a perfect score and an absolute buy recommendation !!!