For concrete core bit, the typical diameters are from 25mm to 600mm, and the typical working lengths are from 200mm to 450mm.
ສໍາລັບ bit ຫຼັກສີມັງ, ໃນເສັ້ນຜ່າສູນກາງປົກກະຕິແມ່ນໄດ້ມາຈາກ 25mm ກັບ 600mm, ແລະຄວາມຍາວເຮັດວຽກປົກກະຕິແມ່ນໄດ້ມາຈາກ 200mm ກັບ 450mm.