I could not find any relevant search results that provide details about a specific spa product, including its positive and negative effects, ingredients, or materials. However, I found some information about the spa industry in general. The search results also include information about essential oils storage, hazardous waste products, and Patanjali Herbal Kajal, but none of these are related to a specific spa product. The other search results are either irrelevant or do not provide any information related to the question.