This set of resistance bands are strong, well made and solid.  I've only used them for a few days but the quality appears to be there to this point.  The accompanying booklet  provides 18 different exercises, some using a door to secure the bands and others that can be done by standing on them.  An anchor is provided that allows the bands to be secured to a closed door although it does not seem to work on all doors (depends on clearance available and how tight the door is to the frame).  However, the anchor is secure and solid.