Potterton Performa SL PCB 5110550. Part No. 5110550. Potterton Performa SL 9 SL (GC No. 41-592-05). Potterton Performa SL 12 SL (GC No. 41-592-06). Potterton Performa SL 15 SL (GC No. 41-592-07). Potterton Performa SL 18 SL (GC No. 41-592-08).
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