When lumber is cut at a lumber mill, the thickness is traditionally measured in quarters of an inch. For example, 4/4 equates to 1 inch and 8/4 equates to 2 inches thick.
When you order zebrawood lumber from us, it is surfaced on both sides (S2S), resulting in a loss of about 3/16 of an inch in thickness.
4/4 lumber will come surfaced to 13/16" thick, and 8/4 to 1 & 13/16".
After sanding or shaping, you should be left with about 3/4" workable material.
Looking for thinner material? See Project Ready wood.