MONACOR SP-302E Hi-Fi Bass-Midrange Compact Bass Speaker in Two Way Construction, Ideal for Installation in a Floor or Stand Box, Black, 304 mm: Amazon.co.uk: Electronics & Photo
Amazon.com: Monacor 600W/200Hz Bass 2 Way Crossover Network for PA : Musical Instruments
Bass-reflex tube Monacor BR-30HP, internal diameter 29 mm, lenght 123 mm