It is a 2.54mm 1×40 Right Angle Female Header Strip.
These connectors are bent at a 90° angle, which is suitable for many applications where the connectors are many times like prototyping.
Also, custom PCBs or general custom headers use these types of connectors.SPECIFICATIONS:
Connector : Header Strip
Gender : Female
Mounting Type : Through Hole
Pin Spacing (mm) : 2.54
Contact Material :Phosphor Bronze
Contact Resistance : 20mΩ
Insulation Resistance (MΩ) : ≥1000
1 X 2.54mm 1×40 Right Angle Female Header Strip 20 Pcs
Product Specification, Right here