It's a factory option from Nismo. Basically exactly how described.
they sieze up because of the heat of the exhaust burning off lubricants on the read muffler flat assembly.
If you have an aftermarket exhaust, then that device has long since been scrapped. If you still have the stock exhast (albeit with a Nismo stamp on the rear muffler) then it can be made to work.
Get out the WD40, give it a bath to try to un-sieze it, and then get yourself some high temperature grease, maybe brake pad anti squeel, and apply.
See how you go.
If, on the other hand, you have an aftermarket exhaust, go and buy a NAWS kit, and use the switch for turning on the NO2!!!
BASS OUT