HCPCS Level II code B4104 denotes an additive for enteral formula, such as fiber, used to modify the nutritional composition of tube-feeding regimens. This designation matters nationally because enteral additives affect clinical outcomes for patients requiring specialized nutrition, influence billing and coverage decisions across payers, and can drive utilization and cost patterns in home and institutional care settings. Key payers considered include Aetna, Blue Cross Blue Shield, Cigna, UnitedHealthcare, and Medicare. Readers will find a concise overview of what the code represents, payer coverage context, and clinical service implications for enteral nutrition. The publication summarizes benchmarks where available, highlights policy and coverage considerations affecting reimbursement and documentation, and provides clinical context on when additives like fiber are used in enteral therapy. Data not available in the input will be noted explicitly in the detailed sections. This summary is intended for clinicians, billing professionals, and policy analysts seeking a national-level reference on coding and coverage implications for enteral formula additives.