You can find all the replacement parts and accessories you need for your Specialized bike at Escapa.
The Specialized Tarmac SL5 Internal Seatpost Clamp is an original Specialized replacement part for Tarmac SL5 frames
Internal seatpost clamp for Tarmac SL5 frames
Wedge-style seatpost clamp for Tarmac SL5 S-Works frames, compatible with all SL5 frames featuring an internal seatpost clamp
Titanium screw