The USMC M-76 OTTER AMPHIBIOUS VEHICLE was built by Pontiac between 1942 and 1953 and was first designed for use in snow. When the Otter was sent to Viet-Nam its primary role was amphibious personnel and cargo carrier and it was used extensively when rain and bad weather had helicopters grounded. The 9,000-lb vehicle could carry or drag its weight in rations and ammo. It could slither up a 60% slope, swim at five knots and run flat out at 35 mph.