finevr Electronic Whistles for Referees with USB Charging, 3 Tone High Volume Emergency Whistle for Referee Coaches Teacher, Outdoor Camping Hiking Boating Safety Whistles with Lanyard Squeeze Whistle  (Yellow, Pack of 1)

【Hand Squeeze Button Whistle】Electronic Button whistle can avoid mouth contact, no need to take off your mask which is really helpfull at this particular time! It is perfect for referee coaches, P.E. teacher, marine, outdoor camping, sports competitions, traffic guides, pet training, self Defense Emergency. Independent lithium battery were not sold with the product 【Excellent Quality, High Volume】There are 3-tones with 3 levels to meet different needs. High volume, can provide up to 120-150 dB sound power. Easy to get attention, helps your voice without blowing but also send louder, strong and consistent sound compared with traditional whistles. 【Durable Whistle】The electronic whistle has a rechargeable polymer cell, which can keep sounding for 4 hours. can keep sounding for 4 hours. It is 10 times more durable than ordinary batteries. USB direct charging save the cost of buying batteries. 【Unquine Design with Intelligent light 】Unique oval shaped design with cicada totem, offer you a good sense of grip. The Intelligent indicate lights will be changed according different tones and different volum level . The electronic whistle is made of high-quality ABS environmentally friendly materials, tasteless and healthy.