Great delivery and well packaged. These bands seem of a fairly good quality although I found the overall actual strength in relation to their strength rating in the description to be a mismatch. To say the Red is light is an understatement. The green snapped on first use when being used in combination with all the others but this could be a isolated incident, I don't know? The Blue appeared light and the Black appeared medium. I have purchased 2 more black bands to use in combination with the rest depending on what I using them for and will see how that goes. I would say if you are well strength trained for 12-24 months just get the black (maybe blue) bands and use a 2-1-2 to a 2-1-4 tempo for the strength side of resistance training, although for the price this is a good product to be fair.