A US-made armoured vehicle will protect UK troops better against roadside bomb attacks in Afghanistan and Iraq, the Ministry of Defence (MoD) has said.
US troops have used Cougars in Iraq for the last 18 months
Unveiling one of the Cougars, Defence Procurement Minister Lord Drayson said they were suited to the "more complex" challenges of modern warfare.
Some 100 of them, bought by the MoD, will be delivered to Iraq and Afghanistan over the next six months.
Land Rovers currently used by UK troops have been criticised as "soft targets".
The snatch Land Rovers used at the moment have been blamed for causing deaths to soldiers by not providing enough protection.
The Land Rovers are designed to withstand small arms fire but are vulnerable to roadside bombs or rocket-propelled grenades.
Following a review into their use, Defence Secretary Des Browne announced the Cougar order in July, as well as the purchase of some other vehicles including an extra 100 Vector Pinzgauer vehicles for Afghanistan, adding to 62 in service.
Unveiling the first of the UK-owned Cougars on Salisbury Plain in Wiltshire on Wednesday, Lord Drayson said they offered "the very best in terms of force protection".
The 23-tonne Cougars - which have a top speed of 55mph and a range of up to 600 miles - are extensively used by US troops in Iraq and cost at least £250,000 each.
Their height off the ground and bulk mean they absorb blasts extremely effectively.
"These are expensive vehicles, they are complex and sophisticated, but they are absolutely necessary for the job which we ask our troops to do," Lord Drayson said.
MoD capability manager Maj Gen Dick Applegate said: "It will save lives in Iraq and Afghanistan."