12 inch shock absorb auger bit suitable for the Ardisam Earthquake 2-stroke Post Hole Borer/ Auger, Ardisam Earthquake 6.5hp Post Hole Borer/ Auger, or the Ardisam Earthquake 4.5hp Honda Engine Post Hole Borer/ Auger, which has to be purchased separately.12 inch diameter earth auger with the Ardisam exclusive " Shock Absorb" a replaceable coil shock spring that protects both the user & gear train from the damaging forces of imbedded rocks, roots & other obstructions.