The tennis bracelet is very pretty, the stones have a nice sparkle in the right light and look very nice. The small 2mm size is more suitable for very small wrists as it will look precious and delicate. I would recommend to buy two of 2mm for a wrist 12-16cm and at least 3 or 4 for a wrist of 16+ cm. The larger 4 mm size would be best to have one for small wrists and at least 2 for larger wrists.