Aero seat post.
aluminum 6061 T6 anodized.
Length: 250mm.
Diameter: Aero 27.2mm.
Designed to fit CHASE ACT 1.2 & 1.0 , Chase RSP 5.0, 4.0, & 3.0 (Expert & larger sizes) & ELEMENT (with aero seat tube)

Use the Elevn Aero Seat Post Clamp in the same size 27.2, for the above frames