Covering for architectural openings with brakes in series

A covering for an architectural opening, comprising:

• an extendable material (112) movable from a lowered position to a raised position for covering and uncovering the opening;
• a drive spool (124) mounted for rotation and operatively connected to said extendable material (112) for raising and lowering said extendable material, wherein said drive spool (124) rotates in a first direction to raise said extendable material and in a second direction to lower said extendable material;
• a drive cord (122) having first and second ends, said first end of said drive cord being wrapped onto said drive spool (124);
• and
• first and second brakes (104″), (284) operatively connected in series to said drive cord (122), with said drive cord (122) extending from said drive spool (124) to said first brake (104), and then to said second brake (284), wherein said first brake (104) includes a roller (132) mounted for selective rotation, and said drive cord (122) is wrapped around said roller (132), wherein braking engagement of said second brake (284) with said drive cord (122) tightens the drive cord (122) around the roller (132) of the first brake (104), and wherein pulling on the second end (320) of said drive cord (122) unwinds the drive cord (122) from the drive spool (124) and raises the extendable material (112).