Figure 4.

The importance of mesh thickness for efficient injections. A. In a thin mesh, the needle will simply push the egg over the surface of the mesh. B. Mesh that is too thick will prevent the needle from entering the egg; often this will result in pushing the egg through the mesh and trapping it underneath because the user is forced to use a steeper injection angle. C. The optimal thickness for injection is slightly more than half the diameter of the egg. At the optimal angle, the egg will be released from the needle by dragging the needle over the wall of the well.