A weft thread or weft threads are selected from a plurality of weft thread supply spools in a shuttleless loom for presenting the selected weft thread or weft threads to the gripper of the gripper rod. In order to equip each loom with the required number of weft selector and needle moving devices and in order to make these devices exchangeable, the individual selector and needle moving devices are constructed as insert cassettes which are exchangeable against one another as desired. For this purpose the exchangeable cassette which is equipped with an electric drive motor and preferably also with a control for the electric drive motor, is combined with a carrier and guide mechanism for supporting the cassette and guiding the respective weft presenting needle. Each cassette comprises at least one weft presenting needle and each cassette is individually connected in a releasable manner to the carrier and guide mechanism and independently of all other cassettes.