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Sienna One Piece in Black - 1 - Onia
Sienna One Piece in Black - 1 - Onia

Sienna One Piece

Rib & Tricot


Size Guide


US Size Numeric Cup Bust Waist Hip
XS 00-0 A-B 31-32 24-25 34-35
S 2-4 B-C 33-34 25-27 36-37
M 6-8 C-D 35-36 28-29 38-39
L 10 D 37.5 30.5 40.5
XL 12 DD 39 32 42
Product Details

A sculpting one-shoulder silhouette, the Sienna One Piece highlights the figure by molding and contouring to the curves in the most flattering way. It has a built-in shelf bra for supportive hold, moderate coverage at the back and a bias-cut center seam to draw the eye to the narrowest point on the waist.

  • Built-shelf bra
  • One shoulder design
  • Bias-cut center seam
Fabric & Care
80% Polyamide 20% Lycra. This textile combination features a flat ribbed swim fabric stitched with our classic tricot, which is durable, resists pilling and provides a second-skin fit. The textures work together perfectly to create dynamic swimwear silhouettes.
Hand wash cool water. Do not bleach. Do not tumble dry. Hang dry. Do not iron.
Shipping & Returns

U.S. Shipping

FREE FedEx SmartPost delivery
2-9 business days

FedEx 2-day delivery
2 business days, $12

Expedited orders placed after 12pm EST will be shipped the following business day.

International Shipping

All International orders are shipped via FedEx International Economy. All International orders will initially be shipped to this address:

FedEx Cross Border Distribution Center
95 Mayhill St - Suite G
MBMB #341387
Saddle Brook, NJ 07663
United States

Once processed for International shipment, your order will be shipped to your International address.

All duties and taxes are calculated at checkout. The duties and taxes are based on the items you ordered, your ship to address and the value of your purchase. All duties and taxes are non-refundable.


Onia offers returns for all full price merchandise for U.S. customers within 14 days of the delivery date. To initiate a return, please click here.

International orders may not be exchanged.

All sale items marked "final sale" may not be returned or exchanged.