High quality 2m GRP Tunnels tunnel with diameter 185mm - suitable for BOW60, 75 & 95 thrusters.
Practical tests demonstrate that acoustic material type ARM can help to reduce bow thruster noise. A coat of ARM compound, or a layer of sheet material around the tunnel can reduce the sound level by about 3 dB(A). Two layers can create a reduction of up to 7 dB(A).