4-O-[(2R)-glycerylphospho]-N-acetyl-beta-D-mannosaminyl-(1->4)-N-acetyl-alpha-D-glucosaminyl di-trans,octa-cis-undecaprenyl diphosphate + n CDP-glycerol = 4-O-{[(2R)-1-glycerylphospho](n)-(2R)-1-glycerylphospho}-N-acetyl-beta-D-mannosaminyl-(1->4)-N-acetyl-alpha-D-glucosaminyl undecaprenyl diphosphate + n CMP + n H(+) — reaction