Ceredi lever expansion plug for Ø 23 mm holes - water tank of motorhome, caravan and boat
- Ceredi lever expansion plug for Ø 23 mm holes in water tanks. Insert it into the hole and press the lever down, and the rubber expands to seal the opening. A nut lets you set the clamping force.
The Ceredi expansion plug closes a round hole with a diameter of 23 mm, for example the drain or vent hole of a water tank in a motorhome, caravan or boat. It needs no thread and no glue. You insert the red rubber part into the hole and then lower the black lever. The lever compresses the rubber along its axis, so it expands sideways and presses against the edge of the hole. When you want to drain the water, you lift the lever and pull the plug out. A nut under the lever lets you adjust the clamping force to suit the hole.

Key features
- for holes with a diameter of 23 mm
- opens and closes with one movement of the lever, no tools needed
- rubber plug expands when the lever is lowered
- adjusting nut for the clamping force, expands up to approx. 25 mm
- rubber plug, plastic lever
- colour: red plug, black lever
- for water tanks in motorhomes, caravans and boats
How it works
- With the lever raised, the rubber is approx. 23 mm wide and slides easily into the hole.
- When you lower the lever, the rubber is compressed and expands to approx. 24 mm, filling the hole tightly.
- If the plug holds too loosely, tighten the adjusting nut. The rubber then expands further, up to approx. 25 mm.
- To remove the plug, lift the lever. The rubber returns to its original shape and the plug comes out easily.
Where it is useful
The plug works wherever a tank wall or bushing has a smooth, round Ø 23 mm hole. Most often it closes the drain hole of a fresh or grey water tank in a motorhome or caravan, and drain holes on boats. It is also handy as a spare when the old plug has cracked, got lost or its rubber has lost its elasticity. You do not need to replace the bushing or the tank, just a new plug of the same diameter.
Fitting and adjustment
- Measure the hole. This plug is for 23 mm holes.
- Clean the edge of the hole from deposits and remains of an old seal.
- Raise the lever and insert the rubber into the hole up to the collar.
- Lower the lever all the way.
- Check that the plug cannot be pulled out. If it can, raise the lever, tighten the nut by half a turn and close it again.
- Fill the tank and watch the hole for a few minutes.
Choosing the size
Lever expansion plugs come in several diameters. Measure the hole with a caliper before you buy. For a hole of 23-25 mm, choose this plug. There are separate versions for 33 mm and 42 mm holes, see the links below. A plug that is too small will not lock even with the nut fully tightened, and one that is too large will not fit into the hole.
Use and care
- Before winter, drain the water and leave the plug open or removed so the rubber is not compressed all the time.
- From time to time wipe the rubber with a damp cloth and remove sand from the edge of the hole.
- If the rubber has hardened or cracked, replace the whole plug.
Related products
- Lever expansion plug Ø 33 mm - for holes with a diameter of 33 mm
- Lever expansion plug Ø 42 mm - for holes with a diameter of 42 mm
Technical data
| Feature | Value |
|---|---|
| Brand | Ceredi |
| Manufacturer article number | 2532 |
| Type | lever expansion plug |
| Hole diameter | 23 mm |
| Rubber diameter when closed | approx. 24 mm |
| Adjustment | nut, expands up to approx. 25 mm |
| Height with lever raised | 94 mm |
| Height when closed | 54 mm |
| Material | rubber, plastic |
| Colour | red plug, black lever |
| Fitting | no tools, no thread or glue |
| Use | holes in water tanks, motorhome, caravan, boat |
Questions and answers
Does the plug fit a 25 mm hole?
Yes, with the adjusting nut tightened the rubber expands to approx. 25 mm. For 33 mm and 42 mm holes choose a larger version of the plug.
Do I need tools to fit it?
No. You insert the plug into the hole and close it with the lever. You only touch the adjusting nut when you want to change the clamping force.
Can I use it to close the drain hole of a tank?
Yes, that is a typical use. Lifting the lever releases the plug, so you can drain the water without unscrewing anything.
What should I do if the plug leaks?
Check that the edge of the hole is clean and smooth. Then tighten the nut so that the rubber presses harder against the walls of the hole.
How do I remove the plug?
Lift the lever. The rubber returns to a diameter of approx. 23 mm and the plug comes out of the hole.
Manufacturer
Ceredi di Ceredi Giovanni & C. Snc, Via del Lavoro 10, 48011 Alfonsine (RA), Italy.




