REDUCTION RINGS KIT FOR LIAERBA CUTTERS UNIVERSAL MOWER RINGS: 1 / 3/8 = 25.4 / 9.5 mm , 1 / 7/6 = 25.4 / 11.1 mm , 1 / 1/2 = 25.4 /12.7 mm , 1 / 5/8 = 25.4 / 15. 9 mm , 1 / 13/16 = 25.4 / 20.6 mm MODEL - TECHNICAL SPECIFICATIONS LENGTH - mm CENTRAL BORE - mm OUTER BORE - mm CENTRAL BORE INDEX - mm CODE: 13271597 ORIGINAL CODE - SR