Bought a iv10ba9 noise reduction semi solid wood internal door to replace our $40 internal standard bedroom door. Guaranteed to reduce sound. Did not reduce it one iota. Have the original door and have had it tested against this $400+ door. They seemed so convincing when they sold us the door but now do not want to know - have put the phone down on us several times - refused to put us through to manager and will not respond to even our complaints by email. We are taking the matter further now but buyers beware