The original retainers weight 8,6g and the titanium retainers weight 4,9g, 45% lighter. 16 Oversized Valves + 16 Titanium Retainers by ABUSO. 16 Retainers made of best grade titanium (Grade 5). These valves are 30mm (1,5 mm oversize) and 26mm (1,0 mm oversize).