This top quality lightweight, dual stemmed cam has proved to be very popular and it is easy to see why. The 4CU is quick and easy to place; it also offers stable secure protection across a variety of crack features. There are 11 different sizes in the range which fit a huge array of crack shapes and sizes, in fact anything from half an inch (13mm) to a meaty 4 Inch (100mm). We have even put in two extra intermediate sizes, 1.25 and 1.75, which slot in between the most commonly used sizes of 1, 1.5 and 2; just what you need for dealing with that awkward crack width that runs between rattley finger jams, to ring locks and on to narrow hand size. There are lots of interesting technical details which give 4CUs the edge on other double stemmed cams. Some of this might seem a bit techy, but it really will make a difference to how the cam performs at the crag. The free floating, peened axle for example reduces stress and helps to avoid a sheering torque at the point of impact.