(a) at least one holding plate defining at least one window covering component opening and at least one closure element opening for receiving the respective window covering components and the closure elements therethrough and holding them in position for sizing;

(b) at least one cutting die being disposed adjacent to at least one corresponding window covering component opening, each of the at least one cutting die defining a die opening corresponding to the corresponding window covering component opening, said die opening receiving therethrough the corresponding window covering component, wherein the at least one cutting die is mounted to the apparatus for pivotal movement with respect to the at least one holding plate; and

(c) a cutting arm moveable relative to said holding plate, said cutting arm being operable to cut the closure elements extending through the at least one closure element opening;

wherein the at least one cutting die and the cutting arm are coupled to a driving means operable to reciprocally engage the at least one cutting die to pivot, and the cutting arm to slide with respect to the holding plate, thereby sizing the respective window covering components and closure elements;

wherein the apparatus comprises a base that is operable to receive in fixed engagement thereto the at least one holding plate and the at least one cutting die from a plurality of different holding plates and cutting dies corresponding to a plurality of different window covering components and covering element sizes and profiles, thereby defining a modular structure for accommodating a plurality of different holding plates and cutting die arrangements for sizing different window coverings having window covering components and covering elements of different sizes and profiles;

selective actuating means coupled to the driving means, wherein the selective actuating means is operable to permit the reciprocal engagement of the at least one cutting die and of the cutting arm to be selectively determined; and

wherein the driving means includes an elongate member to travel a defined distance in a direction of the sizing of the window covering, and wherein the elongate member is coupled with one or more actuating elements disposed along the length thereof, and wherein the at least one cutting die and the cutting arm are also coupled to the elongate member such that the actuating elements are operable to selectively and reciprocally engage each of the one or more cutting dies and the cutting arm based on the position of such actuating elements along the length of the elongate member.