Right Bert Birdcage Adj Birdcage Adjustable Rh (Modified) Bert Transmission Blue/Gold (Right Side) Bert'S Circle Track Dynamics Adjustable Birdcage Ctd-050-R Was Designed For Smart Tube Installation On Northeast Modifieds Such As Teo And Bicknell Race Cars. These New Birdcages Are Truly The Hot Setup. Located By Special Keys Which Fit Into Keyways In The Bracket, Birdcage Timing Is Fast And Repeatable. The Keys Act As A Fuse To Shear On Hard Impact Usually Avoiding More Serious Damage To The Tubes And Suspension.