An Undermount Quartz Sink Built for Serious Kitchen Work
The Karran QU-670 is an extra-large single bowl quartz composite kitchen sink designed for undermount installation in granite, quartz, and solid surface countertops. With an uninterrupted 9-inch-deep basin in Black, it handles the kind of cooking and cleanup that a divided bowl simply cannot.
Key Features
• 80% quartz, 20% acrylic resin construction delivers a hard, dense bowl that resists the scratches and stains of daily kitchen use.
• Extra-large single bowl accommodates full sheet pans, large stockpots, and oversized cutting boards without a center divider in the way.
• Undermount installation places the rim beneath the countertop so the surface wipes directly into the bowl.
• No faucet deck means the faucet and any accessories mount through the countertop, keeping the bowl unobstructed.
• Black finish coordinates with matte hardware and dark countertop palettes and holds up to visible water spots better than lighter colors.
• Highly chip and heat resistant quartz composite stands up to dropped cookware and hot pots set in the bowl.
Where This Sink Earns Its Place
An extra-large single bowl suits kitchens where volume and uninterrupted workspace matter more than workflow separation. Batch-cooking households fill the basin for soaking and rinsing large batches of produce. Avid bakers drop full sheet pans in without angling them past a divider. Entertainers clear a full sink load of dishes into one deep, wide bowl without shuffling stacks between sides. For any of those scenarios, the undivided interior is the point.
Undermounting beneath granite, quartz, or solid surface countertops leaves the countertop edge as the sink's finished border, so spills wipe straight off the counter and into the bowl. This is a conventional undermount installation, not a seamless rim installation. The faucet and soap dispenser mount through the countertop behind the sink, since the QU-670 has no integrated faucet deck.
Quartz Composite in Black
Karran's quartz composite is 80% natural quartz crystals bound in 20% high-performance acrylic resin. The result is a material that is highly scratch, stain, chip, and heat resistant — noticeably harder and denser underhand than a single-material acrylic bowl. The Black color runs through the full thickness of the material, so surface marks don't reveal a contrasting substrate beneath. In a busy kitchen, that consistency matters as much at year five as it does on installation day.
Black also reads differently under task lighting than White or Grey. It absorbs light rather than reflecting it, which can ground a kitchen with light cabinetry and draw the eye toward bold countertop veining. It is a deliberate design choice, not just a neutral default.
Who This Sink Is Right For
Cabinet shops building kitchen packages around dark or two-tone design palettes will find the QU-670 a reliable specification: it fits a 33-inch minimum sink base, drops into a standard undermount cutout, and ships in a single Black colorway without special-order delays. Designers specifying for clients who prioritize uncluttered countertop lines and maximum bowl capacity will appreciate that the faucet deck is absent — every inch of the 31-5/8-by-19-1/8-inch footprint is bowl. Homeowners replacing a dated double-bowl sink who have realized they rarely use both sides at once will find the trade straightforward.
Frequently Asked Questions
Does the QU-670 install with a seamless rim like the Karran Q Series?
No. The QU-670 is a standard undermount sink. It mounts beneath the countertop with clips and silicone, leaving a visible finished countertop edge around the bowl. The seamless rim method is specific to the Q Series and is documented for laminate and solid surface countertops only.
What countertop materials does undermount installation support?
The QU-670 is suited for granite, quartz, and solid surface countertops — materials that hold a finished edge at the cutout. Laminate countertops require the seamless Q Series method rather than conventional undermounting.
Is a template or mounting hardware included?
Karran QU Series spec sheets state that a template and clips are not included with the sink. A paper template and DXF cutout file are available separately for layout and CNC use.
Where does the faucet mount on this sink?
The QU-670 has no faucet deck, so the faucet, soap dispenser, and any other accessories mount through the countertop. Plan countertop drillings before the cutout is made.
Is a drain or grid included?
The QU-670 is sold as a bare sink. A matching basket strainer, bottom grid, and drain components are sold separately and should be specified before installation.
A Single Bowl That Keeps Up With the Kitchen
The QU-670 delivers maximum basin capacity in a Black quartz composite bowl built to handle real cooking loads — undivided, undermounted, and ready for the countertop it sits beneath.
