Mayor Michael Bloomberg and transportation officials Monday will officially debut Brooklyn's first Select Bus Service line.

Bloomberg will join Transportation Commissioner Janette Sadik-Khan and MTA chair Thomas Prendergast in Flatbush to introduce Select Bus Service between Sheepshead Bay and the Williamsburg Bridge.

The new route replaces the limited B44 bus and runs through Nostrand Avenue, with northbound service shifted to Rogers and Bedford avenues at Flatbush Avenue. The local B44 bus will continue to operate 24 hours a day.

SBS includes bus-only lanes in parts of the corridor and off-board fare payment at curbside ticket machines.