Two seals, two jobs: the vented seal goes on first, the non-vented seal covers the next hole — and both get watched until the casualty is handed off.
At a glance
12 things to know about the HyFin Combo Pack
What is in the pouch, which seal goes on first, and what the evidence shows for vented and non-vented seals.
-
01
One of each, packaged separately
The pack holds one HyFin Vent Chest Seal and one HyFin Occlusive Chest Seal, each individually packaged with a gauze pad for wiping the wound surface, inside one twin foil pouch. Use one and keep the other sealed until it is needed.3
-
02
Marked so you grab the right one
Each side of the pouch is identified by name and color, so the vented and the non-vented seal can be told apart before either is opened.3
-
03
The USMC kit
NSN 6510-01-654-6787 is listed in the federal catalog as the USMC chest seal kit — one occlusive and one vented HyFin seal.6 North American Rescue's USMC Combat Lifesaver Kit carries two of these packs.17
-
04
Vented first, non-vented second
The TCCC Guidelines direct that every open or sucking chest wound gets a vented chest seal immediately, with a non-vented seal used when a vented one is not available, and the casualty monitored for a developing tension pneumothorax.1 In this pack, the vented seal goes on first; the non-vented seal covers the next hole.
-
05
How the HyFin Vent works
The vent is not a valve. There is no adhesive over a central area above the wound or along three channels that run to the edge: rising pressure in the chest pushes air and blood out along the channels, and when the casualty breathes in, the film collapses against the skin and blocks air from entering.3,7 North American Rescue designs the vent to keep working even if two of the three channels are obstructed.3
-
06
How the non-vented HyFin works
The occlusive HyFin closes the hole completely. Nothing gets in — and air building up inside cannot get out unless the seal is burped with its red tab.1,3
-
07
Why vented comes first — the swine data
In 8 pigs with an open chest wound and air added to the chest to mimic a leaking lung, a non-vented HALO and a vented Bolin seal both restored breathing at first; as air kept building, the non-vented seal led to tension pneumothorax in every animal at about 1.4 L, while the vented seal held to 2 L.9 That work moved the Guidelines to vented-first in 2013.8 Practice lagged: in a 2013–2014 Afghanistan registry, most chest seals placed were still non-vented.14
-
08
The HyFin Vent in head-to-head tests
In 24 pigs, the HyFin, SAM and Sentinel vented seals (8 each) all evacuated air and blood.10 On a bleeding chest wound in 26 pigs, the HyFin succeeded in 4 of 6 applications, against 6 of 6 for Sentinel and Russell, 1 of 4 for SAM and 0 of 4 for Bolin.12 A 2021 systematic review reached a consensus recommendation for the HyFin Vent and the Russell seal, while noting how thin the evidence is.13
-
09
Adhesion
Both seals use North American Rescue's enhanced adhesive, formulated for skin covered in blood, sweat, body hair or dirt.3 On soiled live swine skin, the HyFin vented seal held as well as the other leading vented seals, even after about 17 hours of storage at −19.5 °C or 71.5 °C.11 Wipe the skin first — that is what the pads are for.
-
10
Every sealed chest still needs watching
Any seal can fail, and the non-vented one cannot vent at all.12 Increasing hypoxia, respiratory distress or falling blood pressure means burping or removing the dressing, or needle decompression by a trained provider.1
-
11
Registration and origin
The FDA lists the combo pack as an occlusive wound dressing (product code NAD) — FDA-registered, Class I (510(k)-exempt) — labeled single use, not made with natural rubber latex, with a lot number and an expiration date on the label.5 North American Rescue states both seals are made in America and 100% latex free.3
-
12
Civilian use is a real debate
The National Association of EMS Physicians says EMS clinicians may consider a vented chest seal for an open chest wound in a casualty who is breathing on their own — and that in a casualty receiving positive-pressure ventilation, chest seals may be harmful and are not recommended.15 Know which situation you are in.
How to use the combo pack
The sequence from the TCCC Guidelines and North American Rescue's demonstration, in order.
-
1Bleeding first. Massive bleeding comes before the chest — tourniquet or packing first, then the open chest wound.1 Never pack a wound in the chest or abdomen.
-
2Find every hole. Expose the chest and look front, sides and up into the armpits, then roll the casualty and check the back — exit wounds are easy to miss.4 Cover the hole with a gloved hand while you open the vented side of the pouch.
-
3Wipe the skin. Use the gauze pad from the pouch to wipe blood, sweat and debris from around the wound so the adhesive can grip.3,4 Seals go on bare skin, never over clothing.
-
4Vented seal first. Pull the red tab to peel off the backing, center the HyFin Vent over the hole and press it down firmly all the way around.1,3
-
5Non-vented seal on the next hole. Open the occlusive side and seal the exit wound or second hole the same way.1,3
-
6Position the casualty. A conscious casualty can sit up or take whatever position makes breathing easiest; an unconscious casualty who is breathing goes in the recovery position.1
-
7Watch the breathing. If breathing gets harder, oxygen saturation falls or shock develops, suspect tension pneumothorax: burp a seal by lifting an edge with its red tab, or remove it. Trained providers then decompress the chest as the Guidelines direct.1,4
-
8Evacuate and keep checking. A penetrating chest wound can hide internal bleeding — move the casualty toward care early and keep reassessing both seals and the breathing.4
Where it fits
- Through-and-through chest wounds — an entry and an exit3
- More than one hole in the chest wall — vented seal first1
- Kits and units issued to NSN 6510-01-654-67876
- A casualty breathing on their own — the setting the NAEMSP statement addresses15
- Packing — never pack a wound in the chest or abdomen; the seals go over the holes
- Treating a tension pneumothorax — burping, removal or needle decompression does that1
- Clothing, or skin still wet with blood and sweat — wipe first, apply to bare skin
- Casualties on positive-pressure ventilation — NAEMSP advises chest seals may be harmful there15
- Practice — train with a trainer seal and keep live seals for casualties
The evidence
Every study cited above, the seals it actually tested, and how strong the evidence is.
| Study | Evidence type | What was studied | What it found |
|---|---|---|---|
| Schauer et al., J Spec Oper Med 2017 | Human · combat registry | 62 casualties with gunshot or puncture wounds to the chest, Afghanistan, 2013–2014 | 74.2% received a chest seal; most seals placed were not vented, despite the 2013 guideline change |
| Kheirabadi et al., J Trauma Acute Care Surg 2013 | Animal · swine | HALO (non-vented) vs Bolin (vented) on an open chest wound, 8 pigs, serial air injections into the chest | Both restored breathing; non-vented seal led to tension pneumothorax in all pigs at about 1.4 L; vented seal held to 2 L |
| Kotora et al., J Emerg Med 2013 | Animal · swine | HyFin vs SAM vs Sentinel vented seals, 8 pigs each, communicating pneumothorax with air and blood challenges | All three evacuated air and blood; no hemodynamic compromise with any seal in place |
| Arnaud et al., Injury 2016 | Animal · swine skin adhesion | Vented seals on soiled live swine skin; five down-selected (Bolin, Russell, Fast Breathe, HyFin, SAM), then stored ~17 h at −19.5 °C and 71.5 °C | Comparable adherence at room temperature; HyFin, Russell, Fast Breathe and SAM held after extreme storage, Bolin did not |
| Kheirabadi et al., J Trauma Acute Care Surg 2017 | Animal · swine | Five vented seals on a bleeding chest wound (hemopneumothorax), 26 pigs | Success: Sentinel 6/6, Russell 6/6, HyFin 4/6, SAM 1/4, Bolin 0/4 (p = 0.002); one-way valves clogged or detached |
| Paquette et al., J Spec Oper Med 2021 | Expert review · systematic | Systematic review of quantitative chest seal studies, 1990–2020 (6 included) | Consensus recommendation for the HyFin Vent and Russell seals; evidence on individual devices is limited |
| Lyng et al., Prehosp Emerg Care 2024 | Expert review · NAEMSP position | Structured review and position statement on EMS care of traumatic pneumothorax | May consider a vented seal in spontaneously breathing patients; seals may be harmful with positive-pressure ventilation |
| Butler et al., J Spec Oper Med 2013 | Expert review · guideline change | TCCC Guidelines Change 13-02, management of open pneumothorax | Vented chest seal first; non-vented if no vented seal is available; monitor and burp, remove or decompress |
Strongest to weakest: human data, then animal studies, then expert review. The HyFin-specific data are swine studies of the vented seal; the non-vented HyFin has not been tested by name, and no human trial has compared chest seal brands.
How it compares
The combo pack beside the single-type HyFin packs a buyer weighs it against.
| HyFin® Combo Pack | HyFin® Vent Twin Pack | HyFin® (non-vented) | HyFin® Vent — Individual | |
|---|---|---|---|---|
| Seals per pack | 2 — 1 vented + 1 non-vented | 2 vented | 1 non-vented | 1 vented |
| Seal size (excluding tab) | 6 × 6 in. each | 6 × 6 in. each | 6 × 6 in. | 6 × 6 in. |
| Packaged | 7.5 × 4.5 × 0.25 in. folded | 7.5 × 4.5 × 0.25 in. folded | 4.625 × 7.5 × 0.1 in. | 4.625 × 7.5 × 0.1 in. |
| Weight | 2.5 oz | 2.5 oz | 1.44 oz | 1.37 oz |
| NAR item · NSN | 10-0073 · 6510-01-654-6787 | 10-0037 · 6510-01-642-6212 | 10-0015 · 6510-01-532-8019 | 10-0029 · 6510-01-624-0840 |
| TCCC position | Vented first; non-vented as the backup | First choice — vented | When no vented seal is available | First choice — vented |
All dimensions, weights, item numbers and NSNs from North American Rescue.3 The TCCC position row reflects the Guidelines' Respiration/Breathing section.1
Build the system
The single-type HyFin packs, the USMC kit this pack ships in, the other three jobs in the kit — tourniquet, packing gauze, pressure dressing — and a trainer.
Questions buyers ask
Package & specifications
Specifications coming soon. Contact us for detailed product information.
Domestic & Military Shipping
Free Standard Shipping: Automatically applied at checkout on all orders $200 and above within the 48 contiguous United States (CONUS).
APO/FPO Military Addresses: Unconditionally free standard shipping on every order, with no minimum purchase required.
Order Processing & Tracking
Fulfillment Timeline: In stock merchandise ships within 48-72 hours from Florida HQ.
Automated carrier tracking details are emailed immediately upon shipment dispatch.
30-Day Returns & Medical Safety
Returns: Unused, unopened equipment in original manufacturer packaging is eligible for return within 30 days of delivery.
Bio-Safety Notice: To ensure sterility and patient safety, medical consumables with opened or broken tamper-evident seals cannot be returned.
Return Facility: MED-TAC International Corp., 15757 Pines Blvd, Suite 154, Pembroke Pines, FL 33027.
Export Compliance
North American Rescue (NAR) products and rifle hard armor plates are strictly restricted to US and APO/FPO addresses and cannot be exported internationally.
FREQUENTLY ASKED QUESTIONS
Customer Reviews
