Core Drill ngu ai gaw hpa rai ta?

Core drill bit ngu ai gaw, n-gun n rawng ai core structure nga ai drill bit rai nna, n-gun rawng ai drill bit lahkawng (sh) dai hta jan nna lawm ai. Core drill bit a hollow center gaw, jak hte galaw ai shaloi, htu ai ntsin hpe jat bang ya lu ai majaw, htu ai lam hpe shim lum hkra galaw ya ai. Core drill bits ni gaw n-gun n law ai hte aten galu lang ai majaw, n-gun ja ai arung arai ni hpe jak hte galaw na matu htuk manu ai.