This is a 1x12 Lego Technic Brick.

There are a few issues with this piece, however:

• The studs on the top of the piece are slightly too small. This means that the studs cannot effectively grip the bottom of another Lego piece.
• The tubes on the bottom are also slightly too small. This means that the studs of other Lego pieces cannot effectively grip the bottom of this piece.
• The wall that holds the tubes on the bottom in place is too thin, meaning that the tubes could possibly deform if the studs of another Lego piece are misaligned.

Despite these issues, the holes for connector pegs and cross axles work just fine.
Enjoy!