Siptenk Expandable Neoprene Freeze Plugs Kit — 27pcs, 13 Sizes (3/4"–2-1/4") with Steel Hardware

Siptenk 27-piece expandable freeze rubber plug kit supplies 13 precisely sized neoprene expansion plugs and steel hardware for fast, leak-tight sealing of engine freeze/expansion holes.

Keep a ready assortment of expansion plugs for engine work, pressure testing, exhaust sealing, and temporary repairs. This kit gathers a wide span of diameters (from 3/4" up to 2-1/4") and includes the steel bolt, hex nut, plate, O-ring and a durable plastic case so you can match the correct plug to the hole quickly and store components safely between jobs.

Which hole sizes are covered and how do I pick the right plug?

The kit contains 13 plug types that each expand to cover a specific hole-diameter range, so you select the plug whose listed fit range overlaps your hole measurement. Measure the opening accurately with calipers or a ruler and choose the plug whose range includes that size for a secure fit.

• 3/4" plug covers 3/4"–7/8" (19–22 mm)
• 1" plug covers 1"–1-1/8" (25–28 mm)
• 1-1/2" through 2-1/4" plugs cover larger ranges up to 2-3/8" (60 mm)

How does installation work and what tools are required?

Installation is straightforward: remove the old seal, insert the neoprene plug assembly into the hole, then tighten the carriage bolt and hex nut so the steel plate compresses the rubber and expands it outward. Minimal hand tools are needed—typically a wrench or socket to tighten the nut; no specialized presses are required.

• Assemble plug in hole with steel plate facing inside the cavity
• Tighten carriage bolt and hex nut until rubber expands and seals
• Verify sealing by visual check or pressure test if applicable

What materials and longevity can I expect from these plugs?

The plugs combine neoprene rubber for elasticity and a steel/ alloy chassis for rigidity, which balances stretch with durability so the plugs expand reliably without easy deformation. Properly installed and used within recommended temperature and chemical limits, they provide a durable temporary or semi-permanent seal for many maintenance tasks.

• Neoprene rubber resists oil, grease and moderate heat
• Alloy/steel bolt and plate give stable expansion force
• O-ring adds an extra barrier against leaks during pressure checks

What’s included in the kit and how is it stored?

The kit ships with every piece needed for installation plus a compact plastic case that keeps plugs sorted and protected. Each size is stocked in multiples across the 27 pieces, and the container helps prevent lost hardware and damaged rubber during transport or storage.

• 27 expansion plugs across 13 sizes (3/4" to 2-1/4")
• Steel carriage bolt, hex nut, steel plate, and O-ring per assembly
• Lightweight plastic storage box with compartments for each component

Who is this for: The Siptenk 27-piece expandable rubber plug kit is designed for mechanics, DIYers, fleet technicians, and maintenance teams who need a versatile set of freeze/expansion plugs for engine repairs, coolant system work, exhaust sealing and pressure testing. It’s useful for professional shops that require a range of sizes on hand and for home garages that want a dependable, organized selection for occasional or emergency repairs. If you need help choosing the correct size for a specific application, contact Siptenk support for guidance before installation.