MKM Steel Ribs MKM no longer manufactures its Professional Series Rigid Steel Ribs due to the high cost of production in the United States. However, we still have inventory available for the following ribs:S2c, S3b, S5, S6, S7a, S7b, S8a, S8b, S9, S10, S12a, and S12b. Please note that all these shap...