Heavy ICBM

Heavy ICBM is a term that was created in the 1970s to describe a class of Soviet ICBMs (intercontinental ballistic missiles). They were characterized by a heavy throw-weight of 5 to 9 metric tons (hence the word, "heavy," in the name) and a length of over 35 meters, and were thus capable of delivering a large number of warheads in a single MIRV missile.

This term usually refers only to R36/SS-9 Scarp and the R36 M/SS-18 SATAN  missiles.

Deliveries
The SS-9 was silo launched missile capable of delivering warheads of 5 - 18 Mega tons, traveling a distance of up to 15,500 km, these were then replace by the similar SS-18 with payloads of 18 - 25 Mega tons. The silos used for launching were the same for both, once modified.