Fit Framework
OEM size & absorbency guide for private label brands
From Source Period — for brand owners & distributors
Dimensional logic
Two numbers buyers must freeze
Period underwear OEM specs are not cup milliliters. They are garment size plus absorbency band, written against a gusset construction.
Approve a size set and a performance band before bulk. Lifestyle names (everyday, overnight, sport) are merchandising — they do not replace the sheet.
Performance
Absorbency bands (catalog language)
| Band | Typical SKU | Buyer note |
|---|---|---|
| Light | Thong, some hipster | Liner replacement / spotting days |
| Moderate | Everyday brief, bikini | Core daily assortment |
| Moderate–heavy | High-waist, boyshort | Heavier-day pharmacy tiers |
| Overnight / max | Overnight heavy, postpartum | Night and recovery kits |
Lab milliliter equivalents are quoted only when a test file exists. Do not print a capacity number you cannot show.
Grading
Garment size run
Catalog grading is XS–4XL unless your RFQ names a shorter curve. Send the size ratio with the first PO (for example S–M heavy, XL–2XL lighter) so cutting markers match sell-through.
A size set sample is the normal lock before bulk. See the spec guide for what belongs on the sheet.
Construction
Gusset and leak layer
Typical stack: body fabric, absorbent core, leakproof layer, stay-dry inner. Overnight and postpartum SKUs use a longer gusset. Sport shorts quote a stay-put waist.
Fiber content and care copy are packing items — list the languages you need on the private label brief.
Size & absorbency FAQ
How should an OEM brand choose absorbency bands?
Map light / moderate / heavy / overnight to the catalog, then freeze the band on the spec sheet before bulk.
What size run do you grade?
Catalog grading is typically XS–4XL. A narrower S–XL curve is quoted if that is your channel.
Can Source Period build a custom size matrix?
Yes — pattern blocks and gusset length can be adjusted via custom OEM. Typical MOQ from 300 units/SKU.
Where does sizing copy go on packing?
Size chart and care copy ship with the packing brief — see private label.
OEM brand resources
Build your brand's size range with Source Period
Share SKU mix, size curve, and absorbency bands — typical quote in 24 hours.