I guess the bands are called u-collars in Torklift vocabulary. The directions are consistent in the installation manual about use of one u-collar for the two shortest extensions. Here is a snippet out of the manual:
MAKE SURE AND PLACE ONE COLLAR IN
THE MIDDLE OF THE EXTENSION AND THE
OTHER AT THE END AWAY FROM THE
TRUCK. TIGHTEN ALL 1/2” FASTENERS TO
60 FT. LBS. NOW REMOVE PINS TO
ENSURE THE EXTENSION WILL COME OUT.
IT MAY BE NECESSARY TO LOOSEN THEN
RETIGHTEN THE FASTENERS TO REMOVE
THE EXTENSION EASILY. NOTE: 21” & 24”
EXTENSIONS ONLY REQUIRE 1 COLLAR AT
THE END AWAY FROM THE TRUCK