Photograph of the kit. Parts #1–16, 28) 3D-printed parts. Part #17) Silicone tubing, ID: 0.5 mm, OD: 1 mm. Part #18) Stepper motor. Part #19) Laser-cut PMMA sheet. Part #20) Metal rod L: 60 mm, OD: 2 mm. Part #21) Metal rod. L: 20 mm, OD: 2 mm. Part #22) 14G, ½” plastic blunt tip dispensing needle, PTFE. Part #23) 23G, ½” blunt tip dispensing needle. Part #24) 18G, ½” blunt tip dispensing needle. Part #25) 18G, 1” blunt tip dispensing needle. Part #26) Tygon tubing, ID: 0.508 mm, OD: 1.524 mm. Part #27) Flexible shaft coupler. Part #29) Photo interrupter, GP1A57HRJ00F.