This is ShopWorx DUM-DUM butyl rubber tape.

A non-hardening putty rope for sealing anywhere water might get in. Feed a wire through a firewall grommet and pack DUM-DUM round it; mount a camera or antenna and seal the hole behind it. It stays flexible permanently rather than curing hard and cracking, so the seal survives years of vibration and temperature swing.

This is the part that stops a water leak appearing in a footwell two winters after an install.

Specifications

• Butyl rubber
• 3/8 inch diameter round bead
• 15 foot roll

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