New Arrival The Sei dress in blue

The Sei

The Sei Asymmetric Silk Dress — Blue

Name: The Sei Asymmetric Silk Dress — Blue
Brand: The Sei
SKU: TS9091BSAPPHIRE
Price: 969.17 USD
Availability: InStock

$969 USD~~$1,848~~ −47%

Incl. express shipping · excl. duties & taxes — calculated at checkout

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Description

This The Sei dress in cobalt silk features an asymmetric cut with a distinctive strappy crossback design and gathered bust detail. The bodice is defined by draped silk fabric that creates movement and visual interest, while the waist is cinched with wrapped silk detailing. The skirt falls to a sweeping floor length with a natural train. Ideal for evening wear and formal occasions where architectural silhouette and luxe draping create an elegant statement.

Shipping & Returns

- Free expedited shipping on every order, direct from the boutique — typically 2–4 business days to the US, fully tracked worldwide.
- Returns within 14 days of delivery. See Returns Policy here.
- Duties & taxes calculated at checkout — no extra import fees on delivery.

Authenticity Guarantee

Every piece is brand new, sourced directly from Europe's most established luxury boutiques — official authorized retailers for the designers they carry. Authenticity is guaranteed, always.

Standard	XXXS	XXS	XS	S	M	L	XL	XXL	XXXL
IT	36	38	40	42	44	46	48	50	52
FR	32	34	36	38	40	42	44	46	48
US	0	2	4	6	8	10	12	14	16
UK	4	6	8	10	12	14	16	18	20

How to measure: Bust — around the fullest part. Waist — at the narrowest point. Hips — around the fullest part. Compare to the brand's measurements; when between sizes, size up for a relaxed fit.

Waist

Standard	XXXS	XXS	XS	S	M	L	XL	XXL	XXXL
Waist	23	24 - 25	26 - 27	28 - 29	30 - 31	32 - 33	34 - 35	36 - 37	38 - 40

Length

Leg Length	Short	Regular	Long
cm	76	81	86
inches	30	32	34

IT/EU	35	35.5	36	36.5	37	37.5	38	38.5	39	39.5	40	40.5	41	42
US	5	5.5	6	6.5	7	7.5	8	8.5	9	9.5	10	10.5	11	12
UK	2	2.5	3	3.5	4	4.5	5	5.5	6	6.5	7	7.5	8	9
JP (cm)	22	22.5	23	23.5	24	24.5	25	25.5	26	26.5	27	27.5	28	29

Tip: Women's luxury footwear is cut in Italian (EU) sizing. If you're between sizes, or the style is structured/pointed, we recommend sizing up.

Standard	XS	S	M	L	XL	XXL	XXXL
cm	52–53	54–55	56–57	58–59	60–61	62–63	64–65
inches	20½–20⅞	21⅛–21½	21⅞–22¼	22⅝–23	23½–23⅞	24¼–24⅝	25–25½

Note: Measure your head across the mid-forehead where the hat will sit.

Standard	XS	S	M	L	XL
cm	16	17.5	19–20	21.5	23–24
inches	6	6.5	7–7.5	8	8.5–9

Note: Measure around your hand below the fingers and from the base to the tip of your middle finger. Use the larger measurement.

Standard	XXXS	XXS	XS	S	M	L	XL	XXL
cm	60–65	70–75	80–85	90–95	100–105	110–115	120	125
inches	24–26	28–30	32–34	36–38	40–42	44–46	48	50
IT	36	38	40	42	44	46	48	50

Standard	XXS	XS	S	M	L	XL	XXL	XXXL
IT	1–2	3–7	8–12	13–14	15–16	17–18	19–21	22–23
US	1.5–2.25	2.5–4	4.5–6	6–6.5	7–7.5	8–8.5	9–9.5	10–10.25
mm	13.00–13.30	13.60–14.90	15.30–16.56	16.90–17.20	17.52–17.83	18.15–18.47	18.79–19.43	19.74–20.06

Standard	XXXS	XXS	XS	S	M	L	XL	XXL	XXXL	XXXXL	XXXXXL
IT/FR	40	42	44	46	48	50	52	54	56	58	60
US/UK	30	32	34	36	38	40	42	44	46	48	50
JP	00	0	1	2	3	4	5	6	7	8	9
GER/DAN	40	42	44	46	48	50	52	54	56	58	60
Numerical	000	00	0	1	2	3	4	5	6	7	8
Roman	000	00	0	I	II	III	IV	V	VI	VII	VIII
RUS	40	42	44	46	48	50	52	54	56	58	60
Korea	80	85	90	95	100	105	110	115	120	125	130
China	155/76A	160/80A	165/84A	170/88A	175/92A	180/96A	185/100A	190/104A	195/108A	200/112A	205/116A
Lacoste	--	1	2	3	4	5	6	7	8	9	10

Collar Size

Standard	XXXS	XXS	XS	S	M	L	XL	XXL	XXXL	XXXXL
cm	36	37	38	39	40	41	42	43	44	45
inches	14	14½	15	15½	16	16½	17	17½	18	18½

Waist

Standard	XXS	XS	S	M	L	XL	XXL	XXXL	XXXXL
Waist	26–27	28–29	30–31	32–33	34–35	36–37	38–39	40–41	42–45

Leg Length

Leg Length	Short	Regular	Long
inches	30	32	34
cm	76	81	86

IT	36	36.5	37	37.5	38	38.5	39	39.5	40	40.5	41	41.5	42	42.5	43	43.5	44	44.5	45	45.5	46	46.5	47	47.5	48	48.5
US	3	3.5	4	4.5	5	5.5	6	6.5	7	7.5	8	8.5	9	9.5	10	10.5	11	11.5	12	12.5	13	13.5	14	14.5	15	15.5
UK	2	2.5	3	3.5	4	4.5	5	5.5	6	6.5	7	7.5	8	8.5	9	9.5	10	10.5	11	11.5	12	12.5	13	13.5	14	14.5
JP	21	21.5	22	22.5	23	23.5	24	24.5	25	25.5	26	26.5	27	27.5	28	28.5	29	29.5	30	30.5	31	31.5	32	32.5	33	33.5
Korea	210	215	220	225	230	235	240	245	250	255	260	265	270	275	280	285	290	295	300	305	310	315	320	325	330	335
Adidas EU	--	--	36	36⅔	37⅓	38	38⅔	39⅓	40	40⅔	41⅓	42	42⅔	43⅓	44	44⅔	45⅓	46	46⅔	47⅓	48	48⅔	49⅓	50	50⅔	--

Standard	XS	S	M	L	XL	XXL	XXXL
US	6½–6⅝	6¾–6⅞	7–7⅛	7¼–7⅜	7½–7⅝	7¾–7⅞	8–8⅛
UK	6⅜–6½	6⅝–6¾	6⅞–7	7⅛–7¼	7⅜–7½	7⅝–7¾	7⅞–8
cm	52–53	54–55	56–57	58–59	60–61	62–63	64–65
inches	20½–20⅞	21⅛–21½	21⅞–22¼	22⅝–23	23½–23⅞	24¼–24⅝	25–25½

Note: To work out your hat size, measure your head across the mid-forehead, where you expect it to sit.

Standard	S	M	L	XL
cm	20–21.5	23–24	25.5–27	27.9–29.2
inches	7.5–8	8.5–9	9.5–10	10.5–11

Note: To work out your glove size, measure around your hand below the base of your fingers and again from the bottom of your hand to the tip of your middle finger, then choose from the widest measurement.

Standard	XXS	XS	S	M	L	XL	XXL
cm	65	70–75	80–85	90–95	100–105	110–115	120
inches	26	28–30	32–34	36–38	40–42	44–46	48

Standard	XXS	XS	S	M	L	XL	XXL	XXXL
IT	1–2	3–7	8–12	13–14	15–16	17–18	19–21	22–23
FR	41–42	43–47	48–52	53–54	55–56	57–58	59–61	62–63
US	1.5–2.25	2.5–4	4.5–6	6–6.5	7–7.5	8–8.5	9–9.5	10–10.25
UK	B–C–D	E–F–G–H½–I	I½–J–K–L½–M½	N–O	O½–P	Q–Q½	R–S–T	T½–U
mm	13.00–13.30	13.60–14.00–14.30–14.60–14.90	15.30–15.56–16.00–16.25–16.56	16.90–17.20	17.52–17.83	18.15–18.47	18.79–19.11–19.43	19.74–20.06
inches	0.51–0.52	0.53–0.55–0.56–0.57–0.59	0.60–0.61–0.63–0.64–0.65	0.66–0.68	0.69–0.70	0.71–0.73	0.74–0.75–0.76	0.78–0.79

Age (yrs)	Height (in)	Height (cm)
2	33–36	84–92
3	36–39	92–100
4	39–41	100–105
5	41–43	105–110
6	43–46	110–117
8	46–50	117–127
10	50–55	127–140
12	55–60	140–152

Age (yrs)	EU	US	UK	Foot Length (in)	Foot Length (cm)
2	23	7K	6–6.5K	5.5–5.75	14–14.5
2	24	7.5K	7K	5.75–6	14.5–15.25
3	25	8–8.5K	7.5–8K	6–6.25	15.25–15.75
3	26	9–9.5K	8.5K	6.25–6.5	15.75–16.5
4	27	10–10.5K	9–9.5K	6.5–6.75	16.5–17
5	28	11K	10–10.5K	6.75–7	17–17.75
6	29	11.5–12K	11K	7–7.25	17.75–18.5
7	30	12.5K	11.5K	7.25–7.5	18.5–19
8	31	13–13.5K	12–12.5K	7.5–7.75	19–19.5
8	32	1	13–13.5K	7.75–8	19.5–20.25
9	33	1.5–2	1	8–8.25	20.25–21
10	34	2.5–3	1.5–2	8.25–8.5	21–21.5
11	35	3–3.5	2.5	8.5–8.75	21.5–22.25
12	36	4–4.5	3–3.5	8.75–9.25	22.25–23.5

Age (yrs)	Waist (in)	Waist (cm)
2–3	19–20	50–52
3–4	20–21	52–54
4–5	21–22	54–56
5–6	22–23	56–58
6–7	23–23.5	58–60
7–8	23.5–24.5	60–62
8–9	24.5–25	62–64
9–10	25–26	64–66
10–11	26–27	66–68
11–12	27–27.5	68–70

Age (yrs)	Circumference (in)	Circumference (cm)
3–6	19–19.75	48–50
6–9	19.75–20.5	50–52
9–12	20.5–21.25	52–54

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The Sei Asymmetric Silk Dress — Blue

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Standard	XXXS	XXS	XS	S	M	L	XL	XXL	XXXL
IT	36	38	40	42	44	46	48	50	52
FR	32	34	36	38	40	42	44	46	48
US	0	2	4	6	8	10	12	14	16
UK	4	6	8	10	12	14	16	18	20

Standard	XXXS	XXS	XS	S	M	L	XL	XXL	XXXL
IT	36	38	40	42	44	46	48	50	52
FR	32	34	36	38	40	42	44	46	48
US	0	2	4	6	8	10	12	14	16
UK	4	6	8	10	12	14	16	18	20

Standard	XXXS	XXS	XS	S	M	L	XL	XXL	XXXL
IT	36	38	40	42	44	46	48	50	52
FR	32	34	36	38	40	42	44	46	48
US	0	2	4	6	8	10	12	14	16
UK	4	6	8	10	12	14	16	18	20