Darice Sports Officiating & Coaching Whistles - 4 Pack - Stainless Steel High-quality whistles for sports officiating and coaching All stainless steel construction resists corrosion; 1-1/2" length x 5/8" width Natural rubber ball won't absorb moisture, produces classic warble Sounds consistent with its attention-getting shrill whistle; includes ring for lanyard Set of four whistles - an outstanding value for schools or special events