Great replacements for the rusted original old seat bracekts and a good upgrade. Prospect-D seat brackets are a direct replacement and help save you time and ease of trying to salvage the original brackets. The rear bracket has been redesigned to mimic the front seat backet, eliminating the 3 rear factory seat brackets.
These will fit 240Z and early 1974 year 260Z. Prospect-D as of yet has not confirmed fitment for the 2+2 models (buy at your own risk). These will not fit the 280Z.
These seat brackets are constructed from 16G CRS which is thicker than the factory seat brackets. Prospect-D hand shapes these brackets with use of professional tools. A light coat of weldable rust preventative primer is sprayed at the end to protect until installation time as an option. After all these are made to replace rusted panels, not recreate rusted panels.