Applications: These core bits have extended barrels to drill into deep walls. The smaller diameters will also help electricians and plumbers to drill through double walls in 1 action to fit conduit pipes or plumbing pipes. They are especially useful in the walls of older buildings where the middle may be loose-filled. Once drilled through, the pipe can be inserted as the core bit is withdrawn to help avoid fall-back of the loose fill. They use standard dry core bit 1/2" BSP fittings. Use a power drill without hammer action and with a clutch or torque limiter. The ideal power would be 1kW or more, especially for the 107mm size. A pilot drill is not used with these extended core bits.
1.Are you a manufacturer or trading company?
We are a 10 years manufacturer.
2.How to prove your quality?
We use E6 diamond,Dipea steel wire, passed ISO9001 and SGS,strict quality control and skilled workers.
3.What should I do if the products is not suitable for the market?
Giving us the detailed report first,then we analyze the reason,try to find the solutions.
If it is our problems,we will give you new products.
4.Do you provide free samples?
Small sample is welcomed.
5.Can you provide OEM/OEM services?
Yes, if you need.
Audited Supplier 
){kind=link}
){kind=link}