Entrenching tool An entrenching tool or E - tool is a collapsible spade used by military forces for a variety of military purposes . Survivalists , freedivers , campers , hikers and other outdoors groups have found it to be indispensable in field use . Modern entrenching tools are usually collapsible and made using steel , aluminum , or other light metals . History and development of the entrenching tool . Entrenching tools go back at least to the times of the Roman Legion . Julius Caesar , as well as other ancient writers , documented the use of spades and other digging implements as important tools of war . The Roman Legion when on the march dug a ditch and rampart around their camps every night where established camps were not available . Siege tactics throughout history required the digging of fortifications and often mining of walls was attempted , where saps were dug to a wall ’ s foundation , and collapsing the wall was attempted . In more modern times the siege tactics of the Napoleonic Wars used spades and pickaxe s as entrenching tools to dig trenches towards the walls of the fortification s being besieged , to allow men and munitions to get close enough to fire cannon s at the walls to open a breach . Being too long and heavy to be transported by individual soldiers , entrenching shovels and spades were normally carried in the supply carts ( logistics train ) of a military column ; only pioneer or engineer troops typically carried spades or shovels as part of their individual equipment . This frequently led to situations in which the infantry did not have access to entrenching equipment when it was needed . As one U . S . army infantry officer noted , " the intrenching [ sic ] tools of an army rarely get up to the front until the exigency for their use has passed . " In 1870 , the U . S . Army introduced the trowel or spade bayonet , intended for individual soldiers as both a weapon and an entrenching tool . This was followed by the development of separate trowel and spade tools , small one - hand implements that could be carried as part of a soldier ' s individual equipment . While the entrenching trowel or spade gradually gave way in the U . S . and other modern armies to larger , heavier , and more effective entrenching tools , the concept of supplying each infantry soldier with a means of digging his own entrenchments or breastworks continued as a tactical doctrine . World War I and the contemporary entrenching shovel . During the 20th century , the ancestor of the modern entrenching tool appeared in the form of the handled entrenching shovel or spade , designed to be used with both hands , yet more compact than traditional , full - sized engineer shovels or spades . These tools became extremely important with the introduction of trench warfare . Entrenching tools designed for the individual infantryman soon appeared with short straight handles , T - handles , D - handles , and other designs . Besides being used for digging defensive fighting position s , entrenching tools were used for digging latrines and graves . During World War I , the entrenching spade was also pressed into service as a weapon . In the close confines of a trench , rifles and fixed bayonets were often too long for effective use , and entrenching tools were often used as auxiliary arms for close - quarter fighting . After World War I , entrenching tools were again redesigned to be more compact and lighter in weight . Folding designs became increasingly popular , usually incorporating a fixed handle with a folding shovel head , and sometimes encompassing a pick into the design . Like all individual entrenching tools , they were designed to be easily carried as part of an infantry soldier ' s standard pack equipment . The British 1937 Pattern web equipment added a bayonet lug to their entrenching tool , allowing the spike bayonet to be mounted on the end and converting the e - tool helve into a mine prodder . Modern developments . The United States Army folding spade , or entrenching tool , has evolved from a single fold spade with a straight handle , to a tri - fold design with a modified “ D ” handle design with all steel construction , to a similar light weight plastic and steel tri - fold design adopted by NATO as the standard issue entrenching tool . Other folding variants have also been issued . The latest light weight plastic tri - fold design is thirty percent lighter than the all - steel tri - fold was : instead of . Entrenching tools , if strongly built , can also be used as weapons . Some entrenching tools can be even sharpened on one or both sides of the blade to be used as cutting tools or weapons ; in fact , when used as such , the tool ' s sharp , thick edges are strong enough to cut through flesh and bone . During the Second World War , entrenchment spades were used in close quarters combat between German and Soviet forces . Soviet Spetsnaz units were well trained in the use of the standard short - handled Russian entrenching shovel ( " saperka " ) as a weapon ; by the nature of their missions , such tools were only rarely used for digging or entrenching positions . Modern commando forces , too , are trained to fight with entrenchment tools . Civilian use . Many millions of surplus entrenching tools have made their way into the hands of civilians . They are commonly used for camping , gardening and by war re - enactment groups . Some people collect the older issue entrenching tools as military memorabilia .