We can supply you gear box for cordless impact drills. Can be applied into 10.8-18V cordless drills.
Have both impact funtion and drill funtion
If any interest, please feel free to let me know.

Specifications:
Reduction ratio: 50/15
Maximum torque stiffness / toughness
£ (Nm): 30--13
No load speed (rpm): 0-380/1300
Pounding force
(bpm): 21000
Gear box settings(No): 22+1
Gear box size(mm): 10
Maximum drilling diameter in wood
(mm): 29
Maximum drilling diameter in steel
(mm): 10
Maximum drilling diameter in stone
(mm): 10
Maximum diameter of screw
(mm): 8