Spec Sheet Preview: The Alpha Communications® / TekTone SF503ES Neck Lanyard Pendant features the great range and reliability of 900 MHz in a small, waterproof package. Users can wear the pendant in the shower or bathtub, outside in the rain, or other environments where the pendant may be splashed with water, or momentarily submerged. The pendants have a single-button design with "press and one second hold" activation, making the pendant very easy to use, yet still reduces false alarms. When the SF503ES is activated, it vibrates briefly …