Truth 40684 white nylon multipoint lock keeper used with Maxim Interlock roller system.
3 sets of mounting holes allow for adjustment 

Measurements:
Length: 1-3/4" (44.9mm) 1.767
Width: 5/8" (15.9mm) 0.626
Leg Length: 1/16" (1.5mm)
Overall Thickness: 0.278 (7.06mm)
Handed: Yes, Left & Right as Shown 
Material: Nylon (plastic) 
Color: White 

Priced and sold each.

Markings: 40684, Part number stamped on back (underside)
The best way to figure which one you need is the number stamped on the bottom or leg length. 

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