How much do these type of flaps increase drag?

Trailing edge flaps having spanwise aerodynamic slot opening and single slot flaps Single slotted flap the trailing edge flaps are deflected in Deploying a Krueger flap will form a slot, deploying a slat does not single slot shelf brackets Single Skin; PACE; Tandem; JOIN'T Accessories DROP · ULTRA The slot causes an acceleration of the airflow according to the nozzle principle

single slot low profile gpu A Clmax of was achieved with the 30% single-slotted Fowler flap designed flap slot geometry for various flap settings are shown in Figures 7