Technical Pro Rechargeable Portable 75-Watt Blue Megaphone Bullhorn Speaker w/ Siren & Detachable Microphone - Battery w/Battery a Built-In AC Wall Charger, Good for Trainers, Coaches, Cheer Leaders - Newegg.com
Amazon.com: OUSIKA Portable Megaphone Bullhorn 25W Portable Speaker Megaphone Strap Grip Loudspeaker Record Play Horn Tour Guide Speakers Powerful and Lightweight Amplifiers : Sports & Outdoors
Handheld Bullhorn Megaphone Adjustable 25W for Outdoor Sports - AliExpress