Is Underbody in stock for delivery in Australia?

Yes. Underbody is currently in stock. It ships from a Chem Connect site that holds it, chosen for your delivery address at checkout. Estimated dispatch: 4 business days after you order. Freight is quoted to your postcode at checkout before you pay, with an estimated delivery date where the carrier gives one.

What pack sizes does Underbody come in?

Underbody is available in 20L Drum, 200L Drum. Custom pack sizes can be sourced via the Custom Orders form.

Is Underbody classified as dangerous goods (DG)?

Underbody is classified as Dangerous goods · Class 3 · UN1263 · Packing group III. It ships through approved Australian DG-rated freight carriers compliant with the ADG Code.

Do prices include GST?

Prices are shown in AUD excluding GST, with the price including GST beside each one. GST (10%) is added at checkout, on products and freight together, and shown as its own line on your order and tax invoice. Invoices are tax-compliant for ABN-holding Australian businesses.

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Underbody - Coolants and Lubricants - Sierra - Image 1

Description

Underbody is Sierra's black bituminous rustproofing for the undersides of cars, caravans, trucks, trailers and heavy plant, in 20 L or 200 L drums.

What it does

Bitumen, about 30 per cent, is carried in white spirit (over 60 per cent) to make a black compound that grips the metal and seals it. Sierra describes the adhesion as exceptional and says the coat waterproofs the surface and protects it from water and corrosion. The white spirit makes it a flammable liquid with a flash point of 38ºC, so it travels as a Class 3 dangerous good.

Where to use it

Sierra's list: full underside coating on cars, caravans, trucks, buses and trailers, heavy construction plant, cargo containers and most steel structures. The enclosed door and body cavities on the same vehicle are a job for Topside Cavity Wax. More in the rust and corrosion protection range.

How to use

Wear safety goggles and solvent resistant gloves, and work outdoors or in a well ventilated bay. The vapour is heavier than air and collects in pits and low spots.
Earth and bond the drum and equipment, use non sparking tools and flameproof equipment, and guard against static.
Apply it as supplied to the underside. No application method or coverage figure appears in Sierra's catalogue or SDS; ask us before a first job.
Keep heat, sparks and flame well away until the solvent has gone.
Close the drum tightly and store it locked up.

Safe on / avoid

Do not store it near aerosols, strong oxidants or corrosives. It is harmful to aquatic life, so keep spills and washings out of drains and waterways. Read the Safety Data Sheet before use.

Specifications

Property	Value
Appearance	Black viscous liquid
Odour	Aromatic
Specific gravity	Typical 1.02 g/ml at 15ºC
Boiling point	Typical 149 to 194ºC
Flash point	38ºC (Abel)
Solubility in water	Not miscible
Dangerous goods	UN 1263, Class 3, Packing Group III, Hazchem •3Y

Pack sizes and delivery

20L Drum and 200L Drum. Freight is quoted to your postcode at checkout. Dangerous goods freight applies.

Questions

▸Should I use Underbody or Topside?

They cover different areas. Underbody coats the exposed underside; Topside is the wax for inside doors and body cavities.

▸What can I coat with Underbody?

Sierra lists vehicle undersides from cars and caravans to buses and trucks, heavy construction plant, cargo containers and most steel structures.

▸Is underbody coating flammable?

Yes. Its flash point is 38ºC, the SDS classes it a flammable liquid, and it ships as Class 3.

▸What is in it?

White spirit at more than 60 per cent and bitumen at about 30 per cent.

Safety Information

DANGER Flammable liquid and vapour (H226). Can be fatal if swallowed and enters the airways (H304). Harmful to aquatic life over the long term (H412).

PPE: Safety goggles. Solvent resistant gloves: nitrile for longer contact, PVC or neoprene for splashes. If vapour exceeds the exposure standard, an AS 1716 respirator with an organic vapour filter.
Handling and storage: Flammable: earth and bond all equipment, use non sparking tools and flameproof equipment, and keep heat, sparks and flame away. Vapour can collect in low or confined spaces. Store locked up and tightly closed in a cool, ventilated area out of sun, apart from aerosols, strong oxidants and corrosives. The SDS notes it contains benzene, toluene, ethyl benzene and naphthalene.
First aid: Swallowed: do not make the person vomit; if they vomit, lean them forward or lay them on the left side, rinse the mouth and give liquid slowly, then get medical advice. Eyes: rinse with running water, holding the lids apart, and see a doctor promptly. Skin: remove soiled clothing and footwear and flush with water and soap. Inhaled: move to fresh air and keep them at rest. Poisons Information Centre 13 11 26.
Spills: Remove ignition sources, contain with sand or earth away from waterways, and move small spills into a labelled sealable container.
Dangerous goods: UN 1263, Class 3, Packing Group III, Hazchem •3Y (section 5 of the SDS prints 3Y).
Poisons schedule: No schedule is stated on the SDS.
SDS: Safety Data Sheet dated 6 Sep 2024 attached to this page.