6:3 WINDOW NET
An SFI 27.1 ribbon-type or mesh-type window net is mandatory on
any full-bodied car required by the rules to have a roll cage. Window
net must be securely mounted on the inside of the roll cage, with
the permanent attachment at the bottom. All attachment points
must be designed in an attempt to protect the driver and avoid
contact with track surface or guardwall. Eyelet clips, dogleash
hardware, hose clamps, etc. prohibited. Penetration of webbing,
except as performed by manufacturer, prohibited. Any modification
to net must be performed by manufacturer.

ROLL CAGE
Roll cage mandatory in cars running 10.99 (*6.99) or quicker or any
car exceeding 135 mph. In full-bodied cars, with unaltered firewall,
floor, and body (from firewall rearward, wheeltubs permitted),
running between 10.00 (*6.40) and 10.99 (*6.99), roll bar permitted