Experimental production and modification of handaxes were carried out by D. in an attempt to achieve a better understanding of the characteristics of Acheulian biface byproducts (/lakes) and the impact of the use of different types of percussors. A result of these experiments was the identification of flakes devoid of scar pattern on their dorsal face. A refitting project was then mounted with the aim of examining the role of these dorsally plain flakes within the handaxe reduction process. Refitting resulted in the identification of three different types of such flakes: those whose dorsal face derives from the ventral face of a previously detached flake (when a handaxe was made on a flake); those that were not struck deliberately, but split spontaneously from the bulbar surface of a large flake; and those whose dorsal face derives from a large scar. This article describes the results of a technological analysis of these unique flakes. The reported results may be used in cases in which refitting cannot be carried out to identify biface modification assemblages that exploited large flakes.