on my old box the sku # is 862nss066 . The new one i ordered, the sku # is 862nsl066. are the letters for length?

The difference between the two SKUs is the length. Let me break down the SKU: 862NSSO66 862N is the model number for the item, the first S is the size which is small, the second S is for the length which is short, O is for open toe, and 66 is the color which is crispa.