As another example, the monoclinic space group P2₁/c contains a center of symmetry at (0, 0, 0), a c-glide plane perpendicular to the b-axis at y = ¼, and a two-fold screw axis parallel to the b-axis at x = 0, z = ¼. Due to the center of symmetry, there is a symmetry related position at -x, -y, -z. The c-glide plane is displayed below:

A general position (x, y, z) is first converted by the mirror plane at y = ¼ to (x, ½ - y, z). The new y-coordinate is equal to y + (¼ - x) + (¼ - x). It is then converted to (x, ½ - y, ½ + z) by the translation of ½c due to the translation part of the c glide plane.