Reliable, durable and versatile product protection

Caplugs stocks a diverse collection of plugs to fit a range of products. Find protective solutions for your needs and shop online today.
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Block dust, dirt and moisture
Protective plugs prevent water, oil, dust and other contaminants from damaging your products.
Threaded, non-threaded & more
Find non-threaded parts or plugs made for imperial, metric, BSP, NPT and other common thread types.
Convenient design features
Shop plugs with pull tabs, slotted heads, hanger holes and other features for easier install and removal.
Discover the full catalog of plugs for masking, sealing, finishing and more – available in a wide range of standard materials, sizes, shapes and colors.
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RPO Series SAE Straight Threaded Plugs
The RPO Series of threaded plugs are designed for SAE straight-threaded ports. Featuring a slotted 12-point head for easy install and a molded O-ring to seal and prevent leakage.

High Performance Materials

Protective caps are made using a variety of standard material options, giving our parts different performance features to meet your specific application or working conditions.
  • Low-density polyethelene
  • High-density polyethylene
  • Conductive polyethelene copolymer
  • Static dissipative polyethylene
  • FlexTemp (thermospastic rubber)
  • Recyclable polyethylene
  • Vinyl
  • Flex500TM Vinyl
  • Steel & zinc plate
  • Silicone
  • Neoprene
  • Aluminum
View Material Data Chart
Material temperature ratings range from 150°F to 650°F. Find the best material for your environmental needs.
Material by Temperature
Custom Solutions

Injection molding solutions for unique challenges