Smooth 1/4” grooves spaced 1 1/2” apart.

• HR-100 Cal-Trans 1.5” Straight Grooves – 24.125” x 47.875” (61.27 x 121.6 cm)

• HR-400 Cal-Trans 0.75” Straight Grooves – 12.25” x 48.25” (31.12 x 122.56 cm)