An apparatus for loading one or more donor rolls of a developer unit,
comprising a developer housing having a reservoir for a developer
material, a rotatable first donor roll that delivers the toner onto a
moving photoconductive member, a rotatable first magnetic brush roll that
receives the developer material from the reservoir and delivers the toner
to the first donor roll, and a rotatable second magnetic brush roll that
receives the developer material from the first magnetic brush roll and
delivers the toner to the first donor roll. The apparatus may further
comprise a rotatable second donor roll that receives the toner from the
second magnetic brush roll and delivers the toner onto the
photoconductive member, and a rotatable third magnetic brush roll that
receives the developer material from the second magnetic brush roll and
delivers the toner to the second donor roll.