An apparatus comprises a plurality of bushings arranged and held together in an array; and a plurality of pins residing in the plurality of bushings, wherein the plurality of pins are for transferring samples. Manufacturing tolerances for inside diameters of the bushings and outside diameters of the pins substantially match to allowing the pins to slide freely within the bushings. The plurality of bushings can reside in one or more plates, each of which having plurality of holes, with the plurality of bushings being held together in the array.