SIDE BY SIDE
See prices, running costs, specifications and trade-offs side by side. Choose two to four products of the same type.
Our under-sink reverse osmosis pick
G3P600 Black Faucet / WD-G3P600-Black
$539US price, checkedFast tankless RO with a TDS faucet, but its certification claims are unconfirmed
Check price at Waterdrop for Waterdrop G3P600 Full review →
Under sink reverse osmosis
G3P800 Black Faucet / WD-G3P800-Black
$999US price, checkedFast tankless RO with a 3:1 drain ratio and unconfirmed certification
Check price at Waterdrop for Waterdrop G3P800 Full review →| Criterion | Waterdrop G3P600 | Waterdrop G3P800 |
|---|---|---|
| US price | $539Checked Oct 13, 2026 · Price details in the review | $999Checked Oct 13, 2026 · Price details in the review |
| Three-year ownership estimate | $973.91 Incomplete known subtotal. Not included: installation, energy use. | $1,478.91 Incomplete known subtotal. Not included: installation, energy use. |
| Choose if | A kitchen on city water with a drain and an outlet under the sink, if you want fast RO water without a tank. | A household on city water that wants quick RO flow and less drain water than a 2:1 system. |
| Main trade-off | No certifier listing was found for the contaminant claims, the warranty is one year, and the power draw isn't published. | NSF doesn't list it, Waterdrop doesn't publish the power draw, and the warranty is one year. |
| Key specifications |
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| Exact variant | G3P600 Black Faucet / WD-G3P600-Black | G3P800 Black Faucet / WD-G3P800-Black |
| Dimensions | 18.11 × 5.67 × 17.73 in and 32.4 lb, per the product page's spec table. Waterdrop doesn't say which figure is width, depth or height, or how much clearance you need to swap filters. | 18.11 × 5.67 × 17.73 in and 32.4 lb, per Waterdrop's product page. Waterdrop doesn't say which measurement is width, depth or height, or how much clearance you need to swap filters. |
| Installation | It goes under the sink and needs a cold-water supply, a drain and an outlet. The kit includes the faucet, a 3/8 in to 1/2 in feed water adapter, a 1/4 in drain saddle, 3/8 in and 1/4 in tubing, lock clips, Teflon tape and a power adapter. Waterdrop says installation takes about 30 minutes and doesn't need a plumber. The product page doesn't give the faucet-hole size or any water limits. Waterdrop's extended-warranty terms do. They call for municipal tap water at 14.5 to 87 psi. Inlet water should be 41°F to 100°F, with a pH of 6.5 to 8.5. TDS must be under 750 ppm and hardness under 7 grains per gallon. Well water needs pre-filtration. It's for indoor use only. | It goes under the sink and connects to a water supply line, a drain and its own faucet. The box includes the faucet, a 3/8 to 1/2 in feed-water adapter, a 1/4 in drain saddle, tubing, lock clips and Teflon tape. It also needs an outlet, and a power adapter comes in the box. Waterdrop calls it a 30-minute DIY install that needs no plumbing skills. It's for indoor use only. The product page doesn't give the faucet-hole size or any water limits, and the linked user manual PDF has no searchable text. The only limits Waterdrop publishes are general ones in its extended-warranty terms, not specific to the G3P800. They call for municipal tap water at 14.5 to 87 psi and 41 to 100°F. TDS should be under 750 ppm and hardness under 7 grains per gallon. Well water needs pre-filtration. |
| Materials | Tankless RO system with 8 stages, including a 0.0001 µm RO membrane. Waterdrop lists three replacement filters for it: G3-N1CF, G3-N3CB and G3P600-RO. The box holds the system, filters, faucet, power adapter, tubing and fittings. Waterdrop doesn't list the housing, tubing or faucet materials, or the media in each stage. | A tankless unit that Waterdrop calls 10-stage, built around three replaceable filters: the G3-N1CF, the G3P800-N2RO reverse osmosis membrane and the G3-N3CB. The membrane page describes this as a 3-filter setup with a seven-layer RO membrane. Waterdrop says the membrane is 0.0001 μm, though the membrane page's FAQ says 0.001 microns. The box list includes a UV sterilizer, and the faucet's display shows TDS and filter life. Waterdrop's comparison table marks alkaline mineralization as not included. Housing, tubing and faucet materials aren't listed. |
| Warranty | One-year warranty covering manufacturing defects, per the product page. Waterdrop's service policy says most of its RO systems get a one-year limited warranty and that terms vary by model. For a defect under warranty, Waterdrop says it can take a free return, repair the unit or send a replacement. For a damaged or wrong item, you email Waterdrop with your order details and a photo. Waterdrop also sells an extended warranty, only for products bought on its US site. It doesn't publish the length or price. The extended warranty excludes filters, products bought outside authorized Waterdrop channels, and damage from parts or filters Waterdrop didn't sell. It also requires municipal tap water at 14.5 to 87 psi and 41°F to 100°F. TDS must be under 750 ppm and hardness under 7 grains per gallon. | One year against manufacturing defects, per the product page. Waterdrop's service policy says most of its RO systems carry a one-year limited warranty and that terms vary by model. If it fails from a quality problem during the warranty, Waterdrop will take it back, repair it or replace it for free. The policy's extended-warranty terms apply only to purchases from Waterdrop's US website. They exclude filters and damage from well or river water. They also exclude damage from incorrect installation, use or maintenance, or from unauthorized repairs. The policy asks you to report a defect within 30 days of finding it. It doesn't say how the extended terms relate to the standard one-year warranty. Waterdrop also offers lifetime technical support for eligible models. |
| Returns | 30-day returns from receipt with no restocking fee, for orders within the continental US. Items must be disassembled and repacked the way they arrived. You pay return shipping unless the problem is a quality defect. After 30 days, or for items not in like-new condition, Waterdrop charges a 10% restocking fee. After 30 days it also deducts shipping from the refund. Refunds are processed within 5 working days of inspection. Orders from third-party sellers, including Amazon, don't qualify. If Waterdrop's own price drops within 30 days of purchase, it refunds the difference. | 30-day returns, counted from receipt, for orders within the continental US. Items must be disassembled and repacked as received, in the original packaging with the receipt. There's no restocking fee within 30 days, but you pay return shipping unless the return is for a quality problem. After 30 days, Waterdrop charges a 10% restocking fee and deducts shipping from the refund. An item that isn't like new also carries a 10% fee. If it arrives damaged or wrong, email service@waterdropfilter.com with your order details and a photo. Orders from Amazon and other third-party sellers aren't covered. The policy doesn't say whether an installed system counts as like new. |
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These comparisons use published specifications, not head-to-head tests. Prices and terms are dated. Unknown costs are not zero. Check the exact variant before you buy.