FABTEK FCLC-2 Fin Clamp Hydronic Baseboard Element Additional Fins, 2' Section For 1-1/4" Copper 2 foot section can be sized to fit your needs, eliminates cold spots More durable than original fins, made with heavier gauge metal The 4-1/4" fin will produce 1527 btu's per linear foot of active element 4-1/4" fin fits 1-1/4" copper pipe