S30, S40 and S50 are the products with most global demand in SUNSHINE. There are few people who place under-boards under speakers worldwide but more people are gradually becoming aware of the necessity of under-boards. However, many under-boards are expensive or need to be bought as a set (since there are usually two speakers)which may be why they are not widespread. SUNSHINE’s under-boards are cheap and effective. They are made of pure Magnesium sheets with high-quality Russian Burch.