Check alternative 1B-A Aluminum Optical Breadboards series for availability in stock today. Specifications of both series (1B-AL-... and 1B-A-...) are the same. The only difference is that in 1B-A Breadboards series mounting holes are closer to the edges (12.5 mm), counterbored through holes are also displaced closer to the edges and the fifth additional central counterbored through hole is added.