The Avantone AV10 MLF is a replacement woofer for use with the original Yamaha NS10M monitors.
 
Though these monitors are valued by many mixing engineers and producers, they've been discontinued for a while, and the supply of aftermarket replacement components has dwindled over the years. Thus, Avantone has reverse engineered the original driver for the NS10 in a faithful manner, updating parts only to comply with modern-day RoHS requirements.
 
Taking up the same dimensions and weight as the original low-frequency driver, the AV10 MLF offers a bolt-in, hassle-free installation process. It also provides a nearly exact match with the original NS10 component, from 20 Hz right up to the tweeter-cutoff frequency.