is a lg cosmos 3 lg-vn251s bluetooth 4.0
You should be able to go into Settings>Application Manager>Scroll to ALL and select the bluetooth. It will tell you which version it is.
I'm looking at an LG G2 so your steps might be slightly different, but overall you're looking for Application Manager.
According to these specs:
LG Cosmos 3 (Verizon Wireless) Specs | PCMag.com
the Cosmos 3 has Bluetooth version 2.1+EDR.
