When selecting a Baby Tub Set, safety is the absolute priority. Ensure the material is BPA-free, Phthalate-free, and Lead-free, typically using high-quality PP (Polypropylene) and TPE (Thermoplastic Elastomer) for foldable parts. Look for non-slip surfaces both inside the tub and on the base legs to prevent sliding. For durability, the folding mechanism should be tested for at least 2,000 to 3,000 cycles without cracking. Additionally, prioritize sets that include ergonomic bath cushions or nets to support newborns safely.