Extra tooling arms for the KMG allow you to quickly change attachments by sliding the entire arm and attachment out, and inserting the next arm with a different attachment ready to go. These are a real time saver!
There are no performance differences between the Aluminum and Steel arms. Based on our testing, they run exactly the same with all of our attachments. Here are a few considerations:
Aluminum arms are 1/3 the weight of Steel arms and are much easier to lift.
The Steel arms will take more shop abuse if you are rough on your machinery and tend to drop or bang things together.
Aluminum arms compliment smaller attachments such as the Small Wheel Attachment.
Aluminum arms are more popular and out sell steel by approx 4 to 1.