The bt diverse 7450 trio plus is one of the top of the range models in the new bt diverse range and has a built in digital answering machine if more than one handset is required the bt diverse 7400 extra handset needs to be purchased as wellas one of the top of the range bt diverse cordless phones the bt diverse 7450 is packed full of useful facilities and features it is very similar to the 7410 but the 7450 also has a digital answering machine built in as well it is very reliable and