See How Tiles Stack Up. STAY SAFE WITH SOS: Discreetly trigger an SOS alert to your loved ones in unsafe situations. Range 500ft / 150m 350ft / 105m 350ft / 105m 250ft / 75m. Battery Up to 1 year, Replaceable Up to 3 years, Non-Replaceable Up to 3 years, Non-Replaceable Up to 3 years, Non-Replaceable.
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