Aww, congrats sa baby! Honestly, I'd be careful with second-hand fetal dopplers kasi mahirap ma-verify kung tama pa ang accuracy at condition niya, a few of us in our mum group learned the hard way na hindi reliable ang old units, and it stressed us out more instead of calming us down. Better check with your OB first kung kailangan mo talaga ng doppler, or kung may trusted medical supply shops sa Sta. Mesa na may new ones with warranty para sure ka sa quality!