These models are part of the "KontinuumLAB Instrument Kit" project. I use these models in my MIDI wind instruments, like the KLIKsophone, melodica, ocarina and others. There are several versions of some. The ones named "locking" fit together with the correspondingly named "box ends" from the KontinuumLAB collection. Some are meant to fit two capacitive sensors, for use as a pitch bend controller. For full description / explanation, go to the KontinuumLAB YouTube channel: https://www.youtube.com/channel/UCSvGhrAVvAKpWMsooCTBWZQ. This is the video about the main K.L.I.K. wind instrument, the KLIKsophone specifically: https://youtu.be/M3CBpWtfdIo All of the KLIK instruments are meant to be built using the KontinuumLAB Instrument Kit electronics. The use of 3d printed parts is optional, all instruments can be hand-made as well. I will be selling the "K.L.I.K." kit, as well as instruments based on it, in the webshop at: www.kontinuumlab.com The 3d-printable parts include: mouth pieces, breath sensors, self-flexing melodica keys, wind instrument keys, structural pieces, end pieces for making boxes, membrane instrument "drums", string instrument fret-board sensor bases and even a fully 3d-printed MIDI ocarina. The KontinuumLAB Instrument Kit is still under development. More detailed descriptions, as well as updates and more designs will be published right here.