The 45° Y-type connectors are standard components in aluminum profile stairway platform systems, they come in two specifications which are designed for left and right side of handrail and always used in pairs. This one is for right side.
The right 45° Y-type connector is designed for assembly with 6063-T5 φ40 aluminum tubes, primarily used for 3-way connection at the intermediate structure of starting section of the right side 45° sloped handrail. This diagram illustrates the 3-way connection by the right 45° Y-type connector.