．Have same function with aluminum rear cover with carbon holder,
　but have the advantage of lower cost.
．The Long Hawn's rear cover with carbon holder is manufactured by
　adopting various special hot plasticity plastic materials, and is
　provided with high impact endurance. In addition, it is also the
　high-quality dielectric material certificated by UL.
．Rear cover with carbon holder can withstand the highest condition
　request to the heat, moisture, and conductibility.

Features：

The wise carbon brush holder will send an alarming signal before the carbon wear out.
Then you can renew the carbons before the electric motor be damaged.