What insect is 1.5mm long with 6 legs 2 anteni?

The insect you're describing could be a type of small beetle or a member of the order Hemiptera, such as a tiny aphid or plant bug. Many insects within these groups can be around 1.5 mm in length, possess six legs, and have two antennae. Without more specific details, it's challenging to pinpoint the exact species. However, many small insects in gardens or natural environments fit this description.