This set of Daleks were stranded on the planet Exxilon. Their colour scheme was silver and black, a lighter change to the grey colour scheme seen previously.
The leader of this set of Daleks had orange lights, The Dalek weapons were useless on the planet Exxilon so they created new ones which were a lot thinner (as pictured below).
These Daleks only appeared in the 1974 TV story Death to the Daleks.
Pictures above are from the TV story titled Death to the Daleks