- Graph Tech PRT-952-201-C0 Ratio InvisoMatch Mounting Plates, F-Style 2-Pin Hole (6 pcs.) - Chrome, Ratio InvisoMatch premium installation plates, for Graph Tech Ratio machine heads with 2-pin housing, fits modern F-Style 2-pin mounting system, use your guitars existing mounting holes for a fast, perfect Ratio Installation, 6 pcs., chrome finish EUR 12.00 - See more - Buy online