1.)   Heavy-duty spool has a metal plate molded into the end of the bump knob for extended wear

 2)   Heavy-duty spool can be ordered as a complete string head or as a replacement spool –  

       replacement spool will fit in heads  

3.)     String heads are easier to open than previous models – when unit is opened, the spool   

       remains in cap and spring is retained in housing

4)      Slotted eyelets provide easier loading

5)     Construction allows for easy, straight, push-back reassembly once string is wound – design 

      eliminates loose components

6)   This design operates with less vibration than previous models

7)     String heads are designed with replaceable components, as with competitive string heads, for easier service – eyelets, arbor nut, and spring are all replaceable where needed

8)  Comes with steel insert – greatly increases the durability of string head, especially in commercial applications with heavy ground contact