HouserDirect via Amazon offers the Wyao 130dB Personal SOS Security Alarm for $23.59. Coupon code "Y85FH9O4" drops the price to $19.82. Plus, Prime members bag free shipping. That's $140 off list and the lowest price we could find. This alarm doubles as a portable speaker and features a 130dB siren, red and blue flashing SOS lights, flashlight, 3.5mm input, and rechargeable lithium battery with up to four hours of music (or one hour of alarm use) per charge.