working depth and drilling depth

ball and sunk

bottom sealing of sunk-well

counter sunk [head ]rivet

counter sunk [head]screw

counter sunk bolt

counter sunk flat head rivet

counter sunk head

counter sunk head bolt

counter sunk head rivet

counter sunk oval head rivet

counter sunk ovel head rievt

counter sunk rivet

Exogenously Sunk Cost

hull sunk

investment sunk cost

Large-sized Sunk Well

long-distance sunk road

Magnetic Sunk Wedge