[#135/A/B, Diced Beef, Beef for Stewing, Beef for Kabobs]
#135: Diced Beef. This product can be prepared from any part of the beast except shank, detached cutaneous muscles and heel meat. It must be free of bones, cartilage, heavy connective tissue and lymph glands. At least 75% by weight must meet the size specification of at least 0.75 inch and no larger than 1.5 inches, but no piece may exceed 2.5 inches. Fat thickness may not exceed 0.50 inch at any point. Of course, that provided by your local meat market may not adhere strictly to this standard, usually with larger hunks, but that isn't such a problem for home cooks as it would be for a prison kitchen or the like.
#135A: Beef for Stewing. This is a little stricter than #135. 80% must meet the #135 size specification and fat must at no point exceed 0.25 inch thick. The batch from which the photo specimen came from met the spec OK except for quite a few pieces exceeding 2.5 inches - in fact one piece was a whopping 4.25 inches.
#135B: Beef for Kabobs. This one is quite a bit stricter than #135. 90% must meet a size narrowed to 1.00 inch to 1.50 inches, and no surface may be more than 2.5 inches. Further, surface and seam fat must not at any point exceed 0.125 (1/8) inch.
More on Cuts of Beef.