I think short shafted units come with guards and long shafted don't. Either way I don't like them, they're supposed to prevent your fingers getting cut off, but don't protect against many other injuries.
F-250 5.4 V8 stand. cab, tandem trailer
Ferris IS3100Z 61" L Kaw, Hydrocut 36" 13hp Kaw
Shindaiwa T3410, EB8520 Maruyama HT2300, MS047
Stihl FC85, MS192T, 041AV, MS200