Built for the job.
Ultra Flex® seam sealer and adhesive is a solvent and isocyanate free multi purpose sealant. It may be applied by caulking gun or spray equipment and is easily extruded and tooled. 4172 is a moisture curing sealant developed for automotive and industrial applications requiring elasticity, high strength and excellent…
TRANSTAR Ultra Flex 4172 MS is a premium, two-part seam sealer and adhesive formulated for high-strength bonding of panels and structural repairs. Delivered in an 11 oz cartridge with a tan solid paste, it provides a flexible seal that accommodates panel movement while maintaining adhesion on a wide range of substrates.
Key performance features include a short work time of 10 minutes and a cure window of 12-24 hours, achieving approximately 3/16 in (4.8 mm) of shrinkage per 24 hours. The formulation is compatible with aluminum, e-coat, fiberglass, galvanized steel, OEM plastics, polyester, primers, SMC, and standard steel surfaces, offering versatile application across body shop projects.
Safety handling requires a “Warning” signal word designation; use eye protection, chemical-resistant gloves, protective clothing, and a respirator in well-ventilated areas. In case of exposure, follow the first-aid procedures outlined in the SDS.
Why Pros Choose Transtar Autobody Technology MS Premium
- Fast curing and has excellent chemical resistance
- One component/moisture curing
- Adheres to a wide variety of materials, including bonding dissimilar materials
- Designed for direct to metal application
- Permanently elastic in a broad temperature range with virtually no shrinkage
- Paintable up to 2 hr after application
- High strength bonds that can replace rivets and mechanical fasteners
- Odor, solvent and isocyanate free formulation, 99% solids
- Can be applied with caulking gun or air gun
How to Use
Automotive, Industrial
- Clean and degrease the substrate to remove oil, wax, or contaminants; ensure a dry surface.
- Open the cartridge and dispense the paste. Mix thoroughly within the 10-minute work time (pot life).
- Apply a uniform bead of seam sealer/adhesive to the joint using a spreader or trowel. One coat is typically sufficient.
- Allow the material to cure for 12-24 hours (thickness up to 3⁄16 in.) before sanding, priming, or further processing.
Compatibility
Compatible substrates: Steel, Aluminum, Galvanized, Fiberglass, Plastic.
Compatible paint systems: Urethane, Epoxy, Solvent, Polyester.
Specifications
| Part No. | 4172 |
|---|---|
| Product Line | TRM |
| Standard/Approvals | California Pro65 Warning: Cancer and Reproductive Harm |
| Application | Automotive, Industrial |
| Manufacturer | Transtar Autobody Technology |
| Trade Mark | Ultra Flex™ |
| UPC | 845505001028 |
| Brand | TRANSTAR® |
| Applicable Materials | Steel, Aluminum, Galvanized Metal, Fiberglass, Urethane, Epoxy, Polyester, Water Based Primers, Glass, Styrofoam, Many Plastics |
| Composition | 15 to 40% Polymer, 1 to 10% Plasticizer, 5 to 30% Calcium Carbonate, 30 to 60% Limestone, <1% Light Stabilizer, 1 to 10% Petroleum Distillate, 0.5 to 3% Drying Agent, 0.5 to 3% Adhesion Promoter, <1% Catalyst, TiO2, <1% Stearic Acid, <1% Quartz |
| Application Time | 10 min |
| Paintable (Y/N) | Yes |
| Sprayable (Y/N) | Yes |
| Component | 1K/2K |
| Color | Tan |
| Flash Point | >205 deg F |
| Container Size (oz) | 11 |
| Container Type | Cartridge |
| Form | Solid Paste |
| Type | MS Premium |
| Curing Time | 12 to 24 hr |
- Cure Time
- 12-24 hrs (3/16″ per 24 hrs)
- Work Time
- 10 min
- VOC
- 0 g/L
- Shelf Life
- 1 yr
- Substrates
- Aluminum, e-coat, fiberglass, galvanized, OEM, plastic, polyester, primer, SMC, steel
About Transtar Autobody Technology
Transtar Autobody Technology is a trusted manufacturer of professional auto body and refinish products used by collision repair shops and restoration specialists across North America.
Frequently Asked Questions
What substrates can I apply TRANSTAR® Ultra Flex™ 4172 MS Premium Seam Sealer to?
It is compatible with aluminum, e-coat, fiberglass, galvanized steel, OEM panels, plastic, polyester, primer, SMC (sheet molding compound), and standard steel surfaces.
How long does the seam sealer take to cure?
The product reaches full cure in 12-24 hours, achieving a thickness of about 3/16 in. per 24 hours.
What personal protective equipment is required when using this seam sealer?
Wear eye protection, chemical-resistant gloves, protective clothing, and a respirator as recommended in the SDS.
How much working time do I have after dispensing?
The work (open) time is approximately 10 minutes before the material begins to set.
Documents & Safety
- Safety Data Sheet (SDS)
- transtar_4172_specification_sheet.pdf
- TRANSTAR_4172_Specification_Sheet.pdf
Warning – Use protective eyewear, chemical-resistant gloves, suitable clothing (coveralls or apron), and a respirator when handling this product. It is toxic if inhaled or swallowed, can cause severe eye injury, skin corrosion, respiratory irritation, and may affect internal organs and reproductive health. The material is also hazardous to aquatic environments. Always refer to the full SDS before use.
Why Buy from autofxmart
- Authorized distributor — authentic, factory-fresh stock.
- Fast US shipping — most orders ship within 1 business day.
- 30-day returns — buy with confidence.
- Pro-shop pricing — bulk discounts available on request.
- Expert support — questions? Email us at [email protected].
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