This Blackberry Thimble features a domed surface to allow for nearly any angle of application, along with artistry that facilitates additional pushing force. The deep indentations are designed for long-term, sustained use. The drop front on the nail side is engineered to protect your finger from callous. Smaller sizes: 4.5, 5 and 5.5 has a simplified design with finer dimples for delicate fingers. The larger Blackberry is shown for comparison.