Abstract: A device for loading brachytherapy seeds and spacers into a sleeve. The device holds two or more seed or spacer cartridges of different radioactive species and dosage. The user rotates a selector for selecting a desired cartridge and, with each depression of a spring-biased plunger, pushes a seed or spacer into a channel in an inspection area. The process is repeated for the desired number and order of seeds and spacers in sequence to form a strand. The strand can be seen in the channel with the unaided eye through a transparent window. Once the strand is arranged as desired, it is pushed into a sleeve that is held in a removable sleeve holder. If desired, the end portions of the filled sleeve may be cut off using a sleeve cutter to shorten the filled sleeve. The filled sleeve is implanted into patient using a needle.