While not an absolutely essential tool, I highly recommend using crimping pliers to finish crimp tubes and crimp beads neatly and most securely.
These are the crimping pliers I use. Xuron makes the best pliers I have used, particularly for crimping and cutting. They can be used with crimp beads and tubes up to 3mm. The jaws include two grooved openings - use the back groove first to create a "half-moon" shape, then use the front groove to roll the crimp into a bead. Handle includes no-slip comfort grips, tool design and colour of handle may vary.
These pliers are approx 5 1/4 inches long and are sold individually.