The Global Specialties EXP-350 Experimentor Series solderless breadboard has 270 tie points and offers unlimited circuit design expansion though it unique molded-in interlocking edge rails. The EXP-350 utilizes 0.3" DIP spacing, and unique molded-in mounting holes allow for either front or rear mounting. Molded interlocking edge rails on all four sides permit parallel or perpendicular socket arrays, allowing more boards to be added at any point for maximum circuit design flexibility. The integrated bus strips allow for fast connections to power and signal lines. The EXP-350 is made from durable polystyrene and premium nickel silver contacts. The EXP-350 has a heavy-duty Mylar backing to prevent short circuits. Read Less...