New TB3 V3 bracket is designed to avoid the components that mount to the bottom track (as many as possible, it is unknown what configurations are possible).
There are no modifications needed for the current Comfort Company Arm Support wood/foam/t-nuts.
The new TB3 V3 bracket was designed to be equivalent in strength to the current TB3 V2 bracket.
We will continue to offer the current TB3 V2 bracket to customers.
The new TB3 V3 bracket will only be offered as a hardware option (not sold on an arm assembly).

Permobil Inc

Comfort Rehab - Accessories