The Lucky Abec 3 longboard bearings are made with chromium 52100 steel balls, stainless steel shields, triple-honed polished raceways and removable dupont derlin crowns - Basically these longboard bearings are awesome value for money.
Skateboard bearings are what mount your wheels to the axle on the trucks. Bearings determine how smooth and fast your skateboard will roll. Generally, the more money you spend on bearings, the better you'll roll! It is also important to keep your bearings clean to get the most out of them.
Bearings that have been rated under the Abec scale are known as precision bearings. The scale goes from 1 to 9 - The higher the number, the better the bearings!
Don't worry about size with bearings, they are all the same.