It looks like the main pieces of SSAC/SpeedDaddy/etc. eBay headers (I have the original prototype set from when they were DPP, and in similar shape, just upgraded flex to ZZP). They're a clone design of SLP headers, but actually made with better stainless (300 grade vs. SLP's 400 grade). If you have the crossover, you can adapt a downpipe to work on a vehicle.
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