• Off White Cotton Sei Pillow Sham - Overhead Bed View, Micro-Flange Detail | MATTEO
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Sei Sham Single

Sei Sham Single

100% Cotton | 600 Thread Count | Sateen Weave | Garment-Dyed

$50
$125 $50
Sale Sold out

MATTEOX Exclusive, 40% discount auto-applies at checkout.

Color Off White
Size Size guide

Description

Sei shams have a 1/2" micro-flange with double stitch detail and an envelope closure to hold your pillow insert snugly in place.

Contrasting white double stitch detail.

Sham vs. Pillowcase

Shams and Pillowcases are both used to protect pillow inserts, but there are a wide variety of constructions. Typically, shams are more fitted and employ some method of closure to keep the pillow in place, whereas pillowcases loosely encase the pillow and are open on the side.

  • 100% cotton
  • Sateen weave
  • 600 thread count
  • Garment-washed

Fabric

Sei is our highest thread count fabric at 600 TC. We are not myopically focused on thread count at MATTEO. Thread count is one among many measurements of quality in the world of bed linens. The most simple definition of thread count is to take a pair of scissors and cut out a square inch of fabric and count each individual yarn (or thread). This is the thread count and, as such, thread count is simply a definition of the density of the weave. It does not take into consideration the softness of the raw cotton used or the size and smoothness of the yarn, nor does it measure the balance of the weave. Focusing only only thread count is similar to deciding which beer to drink by only measuring its alcohol content.

We have not yet gone above 600 thread count at MATTEO because higher counts typically produce a stiff and dense fabric that does not move or breathe.  All sateens (or satin) fabrics have a face which is softer and a backside which is rougher. This is what creates the "silky" feel that customers love so much. And our customers love Sei because it is one of the purest, softest, and silkiest fabrics on the market.

Care Details

Wash

Wash should be separated into light & dark colors. Do not overload machine as this will damage long cotton fibers. We recommend a lukewarm wash cycle with a gentle detergent & a cool rinse.

Bleach may be used on white cotton bed linens only. Avoid using products that contain whitening agents such as chlorine bleach, alpha hydroxy acids and benzoyl peroxide on garment-dyed items. The reactive dyes used for garment-dyeing are not resistant to these whitening agents.

The largest challenge with garment-dyeing is the truth that it is an art, and not a science. We must allow for a shade variation of +/- 10% from dye-lot to dye-lot.

Learn more about Garment-Dyeing.

Drying

Tumble dry with low heat.Remove bed linens promptly from the machine to reduce wrinkling. For best results, line dry.

Ironing

We at MATTEO tend to prefer a lived-in look, as such, you don't find us ironing our sheets too frequently. If you prefer a crisp looking bed, our cotton bed linens should be pressed while slightly damp using the Lightweight Cotton or Medium setting.

Size
inches cm
King 20 x 36 51 x 91
Queen 20 x 30 51 x 76
Euro 26 x 26 66 x 66

Important Notice

All products purchased from the MATTEOX clearance page are samples that might exhibit visible flaws, including, but not limited to, off-color shades, incorrect threads, and faded edges. Products purchased in the same color might be different tones owing to differences from their respective dye lots. Products purchased at 50% off are eligible for a full refund. Products purchased at 60% off are only eligible for exchanges or store credit. Products purchased at 80% off or below are FINAL SALE.

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Frequently asked questions

What fabric is the Sei Sham made from, and why does MATTEO cap the thread count at 600?
The Sei Sham is woven from 100% cotton in a sateen weave at 600 thread count, which is the highest thread count MATTEO produces. We stop at 600 TC deliberately: counts above that typically yield a stiff, dense fabric that does not breathe or move well. Sei uses the same 120/2 Ne yarn in both warp and weft, which gives the face of the fabric its characteristic smooth, silky hand without sacrificing drape. Thread count measures weave density, not softness of the raw fiber or balance of the construction — so chasing a higher number would not improve the result.

What is the difference between a sham and a pillowcase, and which should I choose?
A sham is more fitted than a pillowcase and uses a closure — in this case, an envelope closure — to hold the pillow insert firmly in place. A pillowcase loosely encases the pillow and is open on one side. Shams are generally chosen for a more finished, structured bed presentation, while pillowcases are the more practical everyday option. If you are dressing a bed that will be seen and styled, the Sei Sham's 1/2" micro-flange and double-stitch detail give the bed a considered, intentional look that interior designers tend to prefer.

What sizes are available for the Sei Sham, and what are the exact dimensions?
The Sei Sham is available in Queen, King, and Euro sizes. Queen measures 20 x 30 inches (51 x 76 cm), King measures 20 x 36 inches (51 x 91 cm), and Euro measures 26 x 26 inches (66 x 66 cm). The envelope closure construction works across all three sizes to keep the pillow insert snug without slipping.

How should I wash and care for the Sei Sham to protect the garment-dyed finish?
Wash the Sei Sham in lukewarm water with a gentle detergent and a cool rinse, separating light and dark colors. Do not overload the machine, as this stresses the long cotton fibers. Avoid any products containing chlorine bleach, alpha hydroxy acids, or benzoyl peroxide on garment-dyed pieces, since the reactive dyes used in our Los Angeles dye house are not resistant to whitening agents. Tumble dry on low heat and remove promptly to reduce wrinkling; line drying gives the best result. Learn more about our garment-dyeing process.

What does garment-washing do to the Sei fabric, and should I expect any color variation?
Garment-washing is done after the sham is fully constructed, not at the fiber or yarn stage. This process opens the cotton fibers and produces the softened, relaxed hand the fabric has from the first night you use it. Because garment-dyeing is an art and not a precise science, MATTEO allows for a shade variation of +/- 10% from dye-lot to dye-lot. This is true of all garment-dyed textiles and is something we are transparent about rather than something we try to engineer away. The result is a depth of color that flat-dyed fabrics cannot replicate.

Is the Sei Sham the right choice for someone who wants hotel-quality pillow shams at home?
The Sei Sham is designed and manufactured by MATTEO in Los Angeles using 100% cotton sateen at 600 thread count, the same construction standard applied across MATTEO's luxury cotton bedding line. The 1/2" micro-flange with contrasting white double-stitch detail and the fitted envelope closure give it the structured, tailored finish associated with well-dressed hotel beds. The reactive-dyed cotton holds color cleanly over repeated washing, which matters for maintaining a consistent look over time. Interior designers who work with MATTEO specify Sei for clients who want that same level of finish at home.

What is the Sei Sham Single Clearance, and what should I know before buying?
The Sei Sham Single Clearance is part of MATTEOX, our clearance program for samples that may carry minor visible variations including off-color shades, slight thread irregularities, or faded edges from the dyeing process. Because we make everything in Los Angeles, occasional imperfections happen, and MATTEOX is how we make those pieces available rather than discarding them. Products marked 50% to 70% off are eligible for a full refund or store credit; products marked 80% to 90% off are returnable for store credit only. A $10 restocking fee applies to all MATTEOX returns.

How does the sateen weave of the Sei Sham compare to a percale weave?
Sateen uses a weave structure where more yarn surface is exposed on the face of the fabric, which produces a smooth, slightly lustrous hand. Percale is a plain, one-over-one-under weave that yields a matte, crisp finish. Sei's 100% cotton sateen at 600 thread count sits at the richer, softer end of the cotton spectrum; MATTEO's percale bedding is the right choice if you prefer a crisper, more breathable feel. Neither is objectively superior — the difference is a matter of texture preference and sleeping style.