The product, its packaging, receipts, and the injury scene are the case. The single most damaging post-injury mistake is discarding the device or returning it to the seller "for a refund" — spoliation arguments follow, and the expert has nothing to examine. Photograph everything, then store the product untouched.
The statute of limitations is generally 3 years from injury (CPLR §214), with a discovery rule for latent exposure injuries (CPLR §214-c) — the clock for a drug or toxic injury runs from when you discovered, or should have discovered, the harm. Warranty claims run 4 years from sale. Mass-market products often mean coordinated litigation elsewhere; whether your New York case belongs in the New York State Supreme Court for the county where the accident occurred or in a coordinated proceeding is a strategic decision made case by case.