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COSLUS E1 Electric Water Dental Pick Flosser

COSLUS E1 Electric Water Dental Pick Flosser

By COSLUS · Water Flossers · Health & Lifestyle · More from COSLUS

  • 600ml removable water tank
  • 12 pressure settings (10-160 PSI)
  • 5 interchangeable jet tips
  • Corded electric (AC powered)
  • IPX7 waterproof

Price not listed

New
Used, refurbished, open-box

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Problems, parts and running costs

Summary

A corded countertop water flosser with a 600 mL reservoir, 12 pressure dial positions and five heads, listed at $42.99 direct from COSLUS. Sort out the model name before you buy: the page this store links to is titled EX1, while the E1 specifications sit on a separate RST5102 page.

Strengths

  • A 600 mL reservoir means fewer refills than the small tanks on cordless flossers.
  • 12 dial positions let you start gently and step the pressure up as it feels comfortable.
  • Two standard jet heads are included, so two people can keep separate everyday tips.
  • A top compartment and a magnetic handle dock store spare heads on the base.
  • Direct from COSLUS at $42.99, well below the Waterpik Ultra at $69.99 and Aquarius at $99.99 list prices.
  • COSLUS lists the E1 in its replacement-parts model selector, and the original leaflet gives unusually concrete care and troubleshooting steps.

Weaknesses

  • The page this store links to is titled EX1, not E1, so confirm the carton model before trusting that tips or size match.
  • Genuine E1 replacement heads showed $9.90 and sold out when checked, and the pack contents are not stated.
  • There is no independent lab test, no measured pressure curve and no E1-specific owner record; the model reached the COSLUS store in August 2026.
  • It is corded, so it needs free counter space and a dry outlet, and it is not shower-safe or travel-friendly.
  • COSLUS names only other models for its ADA Seal, not the E1.
  • Poor technique splashes water around the sink, which the leaflet works around by telling you to lean over the basin.

Verified specifications

ModelE1 (RST5102); COSLUS also lists a 600 mL EX1 page and publishes no cross-reference between the two.
Reservoirdetachable 600 mL (about 20.3 US fl oz), with a fill scale.
Pressure12 marked positions with continuous rotary adjustment; COSLUS advertises 10–160 psi, with no independent measurement.
Modesingle pulse mode. The separate E2 model is the one that adds a massage mode.
Power12V DC, 12W adapter with 100–240V AC 50/60Hz input; corded, with no rechargeable battery.
Included heads2 standard jet, 1 orthodontic, 1 periodontal pocket, 1 toothbrush (5 total).
Controlson/off/pause water slider on the handpiece, pressure dial on the base.
Auto shutoffthe original illustrated leaflet states a 2-minute cycle; a third-party rewrite says 3 minutes.
Dimensions8.54 × 6.57 × 5.2 in, 28.16 oz — listed on the EX1 page, not confirmed for RST5102.
Warranty12 months standard, 24 months if registered within 30 days; accessories excluded.
Full research notes and sources

Which model this is

The name on the box is confusing. COSLUS sells an E1 Single-Mode Professional Countertop Water Flosser, model RST5102, and separately lists a 600 mL EX1 oral irrigator — the page this store links to. Both state a 600 mL tank, but COSLUS publishes no cross-reference, and the EX1 page’s dimensions are not confirmed for RST5102. The E1 is not the cordless C20 or E40, and not the two-mode E2. There is no E1 entry on the COSLUS user-guide page, which lists manuals for other models only.

The listed identifier for this model is ASIN B0HF46MRX8, and it could not be confirmed against a live listing.

Pressure, tips and daily use

The E1 is sold as single-mode, and its 12 knob positions do not mean 12 pulse patterns. COSLUS’s own comparison advertises 10–160 psi, but nobody has published an instrumented dial-to-pressure curve, so treat that figure as a marketing claim rather than a measured output. The kit carries five heads: two standard jet, one orthodontic, one periodontal pocket and one toothbrush, which is not five identical family heads. The comparison leaves the E1 column without a timer or pacer; the leaflet describes a 2-minute auto-stop and a third-party rewrite says 3 minutes, so check the behaviour on the unit you actually receive.

Day to day it is a mains-powered sink appliance: set a gentle pressure on the base dial, use the handpiece slider to pause the stream, and lean over the basin or you will spray the room. The leaflet limits you to plain water below 40°C (104°F) and rules out vinegar and aggressive descalers, so the usual internet advice to clean a flosser with vinegar does not apply here. If the flow drops, the leaflet blames a clogged or deformed nozzle, a blocked or poorly seated reservoir valve, an empty tank or too low a setting, and the first fixes are refilling, reseating the tank and cleaning or replacing the head. Those are service-manual possibilities, not a documented defect pattern. Nobody has published an E1 noise figure or a first-hand reliability record, so there is no failure rate to quote.

Replacement heads and running costs

Electricity is not the expense. The leaflet rates the adapter at 12W, and two minutes a day works out to roughly 0.146 kWh a year, about $0.03 at $0.20/kWh. Tips are the real consumable: the leaflet says replace standard jets and the toothbrush head every 6 months, and the orthodontic and periodontal heads every 3 months. COSLUS lists a genuine E1 head pack at $9.90, but it was sold out when checked and does not say how many heads are inside, so no annual dollar figure is defensible. Do not assume heads from the E2 or E40 fit. COSLUS also sells a generic water-floss power adapter at $12.99, but the E1 connector and output are not confirmed to match, so check before ordering.

Warranty, returns and support

COSLUS’s written warranty runs 12 months, or 24 months if you register within 30 days, and excludes accessories — narrower than the 2-Year Warranty banner on every page. The refund policy asks for contact within 30 days, unused product and original packaging, and marks on-sale items non-returnable, so the marketing line is not a 30-day trial. Support runs weekdays 9 a.m. to 5 p.m. Eastern with a one-business-day response target. For a claim, email support@coslus.com with label photos and your receipt, and state clearly whether you have an E1/RST5102 or an EX1.

Is it worth it?

At $42.99 direct from COSLUS it is cheap next to the Waterpik Ultra at $69.99 and Aquarius at $99.99 list prices, and it wins on pressure steps and tank size per dollar. It loses on what the Aquarius lists: a one-minute timer and 30-second pacer, a massage mode, seven tips and a three-year warranty.

Sources

Manufacturer:

Manuals and guidance:

Independent reviews:

Owner reports:

  • No E1-specific owner threads were found.

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