Check the listing for details. PPG EnviroBase ECH5075 Standard Hardener 1 Quart Can Never Opened + Free Ship 📦. Condition: New. Listed at 148.00 USD. The PPG EnviroBase ECH5075 Standard Hardener is a high-quality automotive paint supply suitable for various painting projects. With a brand name of PPG and a manufacturer part number of ECH5075, this hardener is designed to ensure a durable and long-lasting finish. This 1 quart can of never opened standard hardener is a reliable choice for those looking to achieve a professional-looking result with their automotive paint projects.The PPG EnviroBase ECH5075 Standard Hardener is a high-quality automotive paint supply suitable for various painting projects. With a brand name of PPG and a manufacturer part number of ECH5075, this hardener is designed to ensure a durable and long-lasting finish. This 1 quart can of never opened standard hardener is a reliable choice for those looking to achieve a professional-looking result with their automotive paint projects.