This is one of the 2¼" wide seat rollers and its hardware (order a quantity of three per indoor rower) that run on the top and bottom of the stainless steel tube monorail.
Concept2 Seat Roller - Model A, B Indoor Rowing Machines - Brand New!
NEW! Concept2 Seat Top with Frame and Screws — RowErg, Model C, D and E Rowers
Concept2 Indoor Rower Seat Top with Screws- For Model C, D, & E Rowing Machines.
NEW! Seat Complete with Frame & Rollers - Concept2 Model A, B Rowing Machines
Rowing Machine Seat Wheel 43mm Replacement Roller With 8mm Bearing New Great
