450g (1lbs) box of rubber bands
. . .
These rubber bands are the exact size recommended and used by Performance Designs (large and small) and UPT (tandem).
The small rubber bands are 1 1/4″ x 3/8″ x .070″, the large rubber bands are 2″ x 3/8″ x .070″, the tandem rubber bands are 2″ x 5/8″ x .070″.