sidewall. Shaft Modern handles, more commonly referred to as "shafts," are made of hollow metal. They are usually octagonal, instead of round, in order to provide a better grip. Most are made of aluminum, titanium, scandium, or alloy, but some shafts are still made from other materials, including wood, plastic, or fiberglass. The open end of the hollow shaft must be covered with tape or a plug (commonly referred to as the "butt" or "butt end" of the stick), usually made of rubber. The head of the stick is usually attached to the shaft with a screw to keep it in place. Stick length is governed by NCAA regulations, which require that men's sticks (including the head) be from 40 to 42 inches (102 to 107 cm) long for offensive players, 52 to 72 inches (132 to 183 cm) long for defensemen, and 40 to 72 inches (102 to 183 cm) long for goalies. Offensive players usually prefer their sticks to be the minimum length (40 inches or 102 cm) in order to give them the advantage of having a shorter stick to protect from defensive checks. Conversely, defensive players usually prefer their sticks to be the maximum length (72 inches or 183 cm) to permit them the greatest range in covering their offensive player. In 2016, a rules clarification was made by the NCAA Men's Lacrosse Rules Committee. Questions have arisen regarding the alteration of the shaft circumference. The circumference of the shaft cannot exceed 3 1/2" (8.9 cm). To be clear, added tape to the shaft must not make the shaft exceed this circumference measurement. Women's modern stick In women's lacrosse, the stick dimensions are similar except the pocket depth is much shallower. NCAA rules dictate that the head of a woman's stick may be from seven to nine inches wide, and must be strung traditionally, with a pocket formed by a grid of leather strings. Nylon mesh stringing, long permitted in men's sticks, was recently allowed in women's sticks by the end of 2018. The goalkeeper's stick head may be up to 12 inches (30.5 cm) wide and is allowed to be strung with nylon mesh. The legal depth of a women's stick pocket is determined by the following test: the top of the lacrosse ball, when placed in the pocket, must remain above the top edge of the sidewall. Women's sticks can be 35.5 to 43.25