GoFitResistance Power Tubes - Exercise Bands - Resistance Tube - Strength Training, Home Workout, Portable Exercise

Do these have a chemical or other smell? How bad is it?

Can I use these for powerlifting?

Does this come with a manual? Or does anyone know where I can get a manual or exercises?

which gofit band would be equal to a bodylastics 15 lbs rating? [ which they don't make ] Bodylastics make a 13 blue, and 19 black, but I think they need 15.