Regular Augers are designed for use in most soil types. The AMS regular soil auger is commonly used for obtaining disturbed soil samples at or near the surface and for boring to depths where soil samples may be obtained with a separate soil sampler or soil core sampler. The bits of the regular soil auger are open to allow entry of small soil clumps and relatively small rocks and particles. AMS Signature Series augers feature a heavier thread than the standard 5/8" NC thread AMS augers. The signature series thread is more robust and will connect with only 2-1/2 turns. Please make sure any AMS samplers you intend to use together share a common connection type.