is it ok to buy second hand breathing monitor

Gull • Sat, May 06 • Living in Sydney, Australia. TTC since June 2015 and now over a year later I`m finally pregnant and due June 2017

Our friend has offered us her 11 month old oricom baby sense 2 breathing monitor. She has used this for 11 months and now no longer needs it. Is it ok to buy a second hand breathing monitor or is this like a car seat that we should be buying new?