400 total tie-points: -300 general prototyping tie-points -2 columns of 30 rows of 5 interconnected tie-points -100 power rail tie-points -2 pairs of positive and negative power rails, one pair on each side of the breadboard -25 interconnected tie-points per rail The two columns have a 0.3" (7.62mm) separation which allows for easy placement of DIP style package ICs Board-to-board side connectors on all four sides allow you to connect multiple breadboards together to form larger breadboards -The power rail pairs are attached to the main board with the same board-to-board connectors -You can remove the power rails from the main breadboard and cut the adhesive foam backing to make a smaller breadboard and independent power rail pairs Peel away paper protected self-adhesive foam backing to mount to projects or mounting plates