One Tank Clean product guide
COSLUS C51 Cordless Water Flosser (White)
Travellers who want the spare nozzle stored inside the flosser itself
A light cordless flosser with a 300 ml twist-off tank, four nozzles, six pressure levels over a stated 30 to 130 PSI, and three modes including a press-and-hold Jet burst. A nozzle stores in the base, and no charging adapter is included.
Listing checked . Confirm the model, included parts and availability before ordering.
Published specifications
- Manual: model C51; 300 ml tank; 3.7V, 800mAh, 4.5W, under 72dB
- Manual: water pressure range 30-130 PSI across six levels
- Manual: three modes, Clean, Orthodontic and press-and-hold Jet
- Manual: IPX7 rating; auto shut-off after two minutes
- Manual: box holds 2 standard jet, 1 orthodontic, 1 tongue scraper
- Manual and listing: USB cable only, no charging adapter included
Fit and limits
Strengths
- Manual publishes a pressure range, 30 to 130 PSI, across six levels
- Manual describes nozzle storage in a hole in the base of the unit
- Tank twists off for filling and rinsing, with a wide opening
Caveats
- No charge time or battery runtime is published by any source
- Charging cable is mid-change from USB to Type-C, per the listing
- Manual asks you to clean the tank with a brush the box does not include
A small cordless flosser with four nozzles
The C51 is a cordless rechargeable flosser with the reservoir built into the body. The manual's specification table names the model as C51 and gives a 300 ml tank, and the listing and COSLUS's page both describe the same capacity with a wide, borderless opening for filling.
The manual's package list is precise: one main unit, two standard jet nozzles, one orthodontic nozzle, one tongue scraper, a user manual and a USB cable, with the note that the adapter is not included. That is four nozzles in total, which matches the four tips named in COSLUS's own page title.
COSLUS's Specs panel lists the same accessories and repeats the 300 ml capacity, but its dimensions and weight, 9.05 by 3.54 by 2.36 and 15.2 ounces, do not match the listing's 3.22 by 2.68 by 8.5 inches and 9.44 ounces. The manual adds a 3.7 volt, 800 mAh battery, a 4.5 watt rating and noise under 72 decibels.
Three modes, one of which you hold down
The manual names three modes selected with a mode button, and says you can change mode while the flosser is running. Clean is described as removing debris between teeth, and Orthodontic is described for orthodontic patients, used with the orthodontic nozzle to clean around bridges or braces.
The third, Jet, works differently from the other two. The manual says you keep pressing the power button to start cleaning and release it to stop, and that Jet mode requires no manual shutdown. The listing calls this an intuitive press-to-clean mechanism aimed at quick clean-ups.
The listing multiplies three modes by six pressures to advertise eighteen options. The two continuous modes and the burst-style Jet mode are the real distinction between them, and the manual describes each of the three in a line rather than as a procedure.
Six pressure levels over a published 30 to 130 PSI
The manual's specification table gives a water pressure range of 30 to 130 PSI. The listing and the maker page only count levels, so the manual is the one document that says what those levels deliver. Pressure is changed with its own button rather than a dial.
The manual groups the six levels into three pairs, from the lowest pair, which it names as the place a first-time user starts, up to the top pair. It prints its own wording for each band, and that guidance belongs in the manual rather than in a summary of it.
The manual also says the flosser shuts off automatically after two minutes, and that the tank takes water no warmer than 40 degrees Celsius. Storage is specified between 0 and 40 degrees Celsius at 20 to 85 per cent humidity.
The tank twists off and a nozzle hides in the base
The manual shows the reservoir sliding clockwise and pulling free, so it can be filled under a tap or rinsed on its own. COSLUS's page makes the same point, describing a wide opening and a removable tank that is easier to rinse and clean after each use.
For travel, the manual says to insert a nozzle into a hole in the bottom of the main unit, describing storage for one. The listing instead describes built-in storage holding two nozzles inside the body. Neither source explains the difference, so check the unit itself.
For storage between uses, the manual asks you to wipe the product dry and then stand the main unit upturned inside the tank. It warns that water left inside the unit encourages bacteria, so the drying step is part of the routine rather than optional.
The charging cable is mid-change, and no adapter is supplied
The first bullet on the listing is a product upgrade notice: COSLUS says it is moving from USB to Type-C cables and asks you to confirm you have a compatible Type-C power source before buying. It adds that if the cable supplied does not suit you, contacting them will get the other version sent.
No charging adapter is in the box on either the listing or the manual's package list, so you supply your own. The manual's safety cautions say the appliance is only to be used with the charging cable provided and a power adapter meeting the specified requirements, and the table gives a charge input of 5 volts at 2 amps maximum.
Neither the listing, the maker page nor the English manual pages state how long a charge lasts or how long charging takes. With an 800 mAh cell there is no published runtime to plan around, so treat battery life as unknown until you use it.
Care: water or a neutral cleaner, and nothing acidic
The manual is emphatic about cleaning agents. It says to use only water or a neutral cleaning agent, never caustic or abrasive agents such as vinegar or limescale removers because they may damage the appliance, not to use water over 40 degrees Celsius, and to keep the flosser away from heat and direct sunlight.
After each use it asks you to remove the tank and pour out the water, clean the inside of the tank with a cleaning brush and leave it inverted to air dry, then run the flosser briefly to drain water from the hose. The package list does not include a cleaning brush, so that is one to supply yourself.
The nozzle is to be washed and replaced every six months, the main unit wiped with a soapy cloth but never submerged for cleaning, and the suction tube washed without bending or twisting it. COSLUS's Warranty Information page sets the condition behind the two-year badge: registration within thirty days of purchase extends cover to 24 months, limited to the first purchaser, and excluding accessories, unauthorised sellers, misuse and water damage.
Check the current listing
Confirm the model, included parts and availability before ordering.
Primary sources
- COSLUS product page for the C51 retractable-tip cordless water flosser
- COSLUS C51 user manual attached to the listing (PDF, English pages)
- COSLUS Warranty Information page
Primary sources checked .
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