“Calendar” soles are made by running a continuous sheet of uncured rubber through a dual-roller press. The top roller is etched with a tread pattern while the bottom roller is smooth. Once pressed, the soles are hand cut on a template with a hot knife. The uncured soles are then applied to the upper boot and vulcanized together to form a seamless permanent chemical bond. The calendar soles on all DRYSHOD models are clad over with a rigid puncture-resistant tuck board with steel shank and latex-sponge heel wedge. Calendar soles can be cut in a variety of shapes and contours to suit the use of the model. The inherent low center of gravity on calendar soles provides excellent stability on uneven terrain.