A hose or pipe clamp that locks tightly in place using a custom “toggle latch” mechanism. Can be customized to have any diameter, but may not work as well above 1inch/25mm diameter without some additional customizing. Works especially well for very small diameters that are hard to find standard metal hose clamps for. 

The default model parameters provide an extra 1mm of circumference to the clamp so it can be slipped over your hose/pipe. Locking it in place removes this extra spacing and tightens it down to the target diameter. 

To prevent it from unlocking itself (due to movement, vibration, etc), cut two pieces of a paperclip and insert them through the two locking pin holes as shown here (but bend them so they can't come back out): 

The provided print profile includes diameters from 6-24mm in increments of 2mm, plus 25mm (~1inch). 

Customizing

UPDATE JULY 2025: Makerworld now supports customizing this directly from the website! You should still follow the instructions below related to supports and print orientation though. 

To customize this you'll need to use Autodesk Fusion (free for personal use). You can easily change the diameter, clamp thickness, clamp length, and more. 

To Customize:

• Use the “Download STL” button to download the .f3d file. Open it in Fusion. 
• Hit the “S” key on your keyboard to open the Search box. Search for User Parameters and open that menu. 
• Edit the parameters to suit your needs.
  • I've starred the ones you will most likely want to edit.
• Export the design as a 3MF or STEP file.
• Open the exported file in your slicer. 
• Right-click on the model and click “Split→To Objects” (if it wasn't already split when imported)
• Refer to the provided print profile for print settings. For best results you'll need to manually paint supports  for the Lock object (using the Fill method to paint the two purple areas in the image below) and set the support method for that object to “Tree (Manual).” 

Printing

For best results print in PETG. PLA will probably deform over time under the locking pressure, loosening the clamp; PETG is better at retaining its shape under stress over time. 

The Lock object can alternatively be printed flat, in the same orientation as the Latch object. This will make it stronger and less likely to break, but it comes out with less dimensional accuracy, requires more support cleanup, and make it harder to assemble.