Many modern bicycles use what is called a "cartridge" bottom bracket instead. Sealed cartridge bottom brackets are normally two pieces, a unit holding the spindle and bearings that screws into the bottom bracket shell from the drive side and a support cup (often made of light alloy or plastic) that supports the spindle/bearing assembly on the non-drive side. Other designs are three piece, the spindle is separate, but the bearing cups incorporate cheaply replaceable standard cartridge bearing units. Either arrangement makes servicing the bottom bracket a simple matter of removing the old cartridge from the bottom bracket shell, and installing a new one in its place. Cartridge bottom brackets generally have seals to prevent the ingress of water and dirt. The early Shimano LP bottom brackets from the 1990s had the support cup on the drive side and used loose bearings inside; they could be dismantled and serviced much like cup and cone bearings.[https://www.youtube.com/watch?v=psJxGx3cVR8]