From the seventeenth century to the early years of the eighteenth century, most nations did not specify standards for military firearms. Firearms were individually procured by officers or regiments as late as 1745, and were often custom-made to the tastes of the purchaser. As the firearm gained ascendancy on the battlefield, this lack of standardisation led to increasing difficulties in the supply of ammunition and repair materials. To address these difficulties, armies began to adopt standardised "patterns". A military service selected a "pattern musket" to be stored in a "pattern room". There it served as a reference for arms makers, who could make comparisons and take measurements to ensure that their products matched the standard.