Apico trial radiator cap comes with a 10mm hex head for easy and simple removal or installation with a spanner. Many of the standard OEM cap use a Allen hex key making them very difficult to remove. These new radiator caps are CNC machined for a precision fit using an aerospace grade 6061 T6 aluminium. They also come supplied with O-ring seal. M14 x 1.5 thread, 10mm hex head. FITMENT GAS GAS TXT/PRO/RACING 50 2005 80 2015 125-300 13-22 JOTAGAS/JTG ALL SCORPA SC/TWENTY 11-24 (Not SY) SHERCO ST 10-24 TRS ONE/GOLD/R/RR 16-24