Big-Sert repair kit and Tap Guide M8x1.25 for repairing failed helicoil repairs. For virgin repairs Time-Sert is recommended [smaller hole to be drilled] but Big-Sert can be used.
3 standard 11.7mm long inserts included. I used the other 2 to repair failed helicoil repairs on airhead BMW center valve cover studs for which the 11.7mm long inserts fit perfectly.
New cost $122 + shipping which included 5 inserts.
$75 shipped CONUS includes 3 inserts.