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“C collar” is shorthand for a cervical collar, the neck support also sold as a neck brace. Collar sizes are set by each maker, and the maker documents cited below do not point to a shared standard that defines them. The chart shows what three makers publish and which body landmark each one uses. This page is general product information, not medical advice.
For the wider picture, see the plain-language cervical collar guide and the types and sizing guide for clinics and EMS. Always check your product’s labelling and the maker’s sizing sheet before you rely on any number here.
C collar size chart: what three makers publish
| Maker and product | Size labels | Published dimensions | Measurement landmark |
|---|---|---|---|
| Core Products, Foam Cervical Collar Universal | 2 in, 2.5 in, 3 in, 3.5 in | 24 in long by 1 in thick, with heights of 2, 2.5, 3 and 3.5 in | Chin tip to sternal notch |
| Aspen Medical Products, Aspen collar (adult) | Extra Tall, Tall, Regular, Short | No numeric table; sizes are read from a printed ruler | Highest point of the trapezius to the bottom of the chin, using the printed guide |
| Aspen, pediatric guide | Extra Tall: 2-5 years; Tall: 3-6 years; Regular/Short: 5 years and up | Extra Tall: 26-42 lb (12-19 kg), 35-45 in (89-114 cm). Tall: 27-54 lb (12-25 kg), 37-48 in (94-122 cm). Regular/Short: 36 lb (16 kg) and up, 42 in (107 cm) and up | Weight and height bands; the guide refers to the maker’s Pediatric Collar Instruction Sheet. The same guide lists bands for younger children, not reproduced here |
| ProCare California rigid collar, Small (one distributor listing) | Small | 4 1/4 in height; neck circumference 10-13 in | Sternal notch to chin |
Sources: Core Products product page, Aspen Cervical Collar Sizing Guide (PDF), and a distributor listing for the ProCare product, checked 2026-11-01. The rows are copied from those documents, not from a standard.
How to read the chart
The size label on its own tells you very little. “Regular” for one maker is not “Regular” for another, and a number such as 3 in on Core Products is a collar height, not a neck measurement. Read each row as three separate things: the label, the dimension the label stands for, and the body landmark the maker compares against it.
Height versus neck circumference
The ProCare listing publishes both a collar height and a neck circumference range. Core Products labels its sizes by collar height. Aspen’s adult guide gives neither as a number and relies on its printed ruler, which is accurate only when printed at “Actual Size”.
Which landmark each maker uses
- Core Products: the distance from the tip of the chin to the sternal notch, the small indentation between the collarbones.
- Aspen (adult): a printed guide held against the highest point of the trapezius, read against the bottom of the chin.
- ProCare listing: height is given as measured from the sternal notch to the chin.
Aspen’s guide says its directions are guidelines only and are not offered as medical recommendations.
Equivalence notes: why sizes do not carry across brands
The landmarks differ (chin to sternal notch for two makers, trapezius to chin for Aspen), the size labels differ (inches against words), and a pediatric guide may use weight and height instead. The cited documents give no conversion between them, so do not map “3 in” to “Regular”. Specific product types have their own charts, for example the soft collar, the Philadelphia collar and the Aspen collar; the regulatory background is in the cervical orthosis guide.
Common mix-ups
- Reading a collar height as a neck circumference, or the reverse.
- Using one maker’s chart for another maker’s collar.
- Using an adult size label for a child; Aspen publishes separate pediatric weight and height bands.
- Using a printed sizing ruler that was scaled to fit the page rather than printed at actual size.
What to have in hand before you order or stock
- The maker’s own sizing sheet and instructions for use for that exact product.
- Which landmark that maker measures from.
- The size labels and the dimensions behind them.
- The label on the product in front of you, which governs over any chart.
FAQ
What is a “c collar”?
It is a common shorthand for a cervical collar, a device worn around the neck. This page uses the two terms interchangeably.
Is there a standard cervical collar size chart?
The maker documents cited here do not refer to a standard that defines collar sizes. Each maker publishes its own labels and measurement landmark.
Do cervical collar sizes carry across brands?
No conversion is published in these documents. The makers use different landmarks and different size labels, so use the chart for the specific product.
How does Aspen label pediatric sizes?
Aspen’s pediatric guide uses weight and height bands, for example Tall for 3-6 years, 27-54 lb and 37-48 in. Other makers have their own guides.
Sources
- Core Products, Foam Cervical Collar Universal, https://www.coreproducts.com/products/foam-cervical-collar-universal, checked 2026-11-01.
- Aspen Medical Products, Aspen Cervical Collar Sizing Guide (PDF), https://cdn.shopify.com/s/files/1/1298/6995/files/aspen-collar-pd-sizing-chart.pdf, checked 2026-11-01.
- ProCare California rigid cervical collar, Small, distributor listing, https://markdown.wellbefore.com/products/procare-california-rigid-cervical-collar-small-4-inch-height, checked 2026-11-01.
