Truth 40709 white nylon multipoint lock keeper used with Maxim Interlock roller system.
3 sets of mounting holes allow for adjustment 
Used by Weather Shield and many other window companies

Measurements:
Length: 1-3/4" (44.9mm) 1.767
Width: 5/8" (15.9mm) 0.626
Leg Length: 3/16" (4.7mm)
Overall Thickness: .371 inch (9.42mm)

Handed: Yes, Left & Right as Shown 
Material: Nylon (plastic ) 
Color: White 
Priced and sold each.

Markings: 40709, Part number stamped on back ( underside )
The best way to determine which one you need is the number stamped on the bottom or leg length. 

Related Parts:
556084 - .228 Thick, Flat Bottom RH
556085 - .228 Thick, Flat Bottom LH
556086 - .278 Thick, 1/16" Legs RH
556087 - .278 Thick, 1/16" Legs LH
556088 - .331 Thick, 1/8" Legs RH
556089 - .331 Thick, 1/8" Legs LH
556090 - .371 Thick, 5/32" Legs RH
556091 - .371 Thick, 5/32" Legs LH