The DMX 1-STEP Flooring Underlayment is a high-quality solution for your home improvement needs. This blue underlayment is moisture resistant, waterproof, and mold resistant, making it perfect for basements and below grade installations. Suitable for engineered hardwood, vinyl, and laminate flooring, this 100 sq. ft. underlayment is designed to provide a reliable and durable foundation for your flooring. Made in the United States, this underlayment measures 29"L x 42"W, ensuring a seamless installation over concrete subfloors.