Shaver Razor Retaining Lock Rings. SH50/52 Shaving Heads compatible with Norelco Shaver Series 5000 Rounded and 6000, Latest Version for Refreshed HQ9/50, HQ56/50, and RQ11/50. Shaver Lock-ring Retaining- Semi-Plate Holder for Series 5000 models S5010, S5011, S5013, S5015, S5050, S5070, S5074, S5075, S5077, S5078, S5079, S5080, S5082, S5085, S5090, S5100, S5110, S5130, S5140, S5150, S5203, S5205, S5210, S5211, S5213, S5230, S5231, S5251, S5252, S527.