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GROCO  |  SKU: GRO-BB-1

Groco BB-1 Seacock Backing Block for 3/4" & 1" Seacocks

$69.93 CAD $112.99
Ships By Sun, October 25 Free Canada Shipping over $120

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✔ Locally owned in Nanaimo, BC
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The Groco BB-1 backing block gives a 3/4" or 1" flanged seacock a solid, even base against the hull. It sits between the seacock flange and the hull, spreading the load and giving the mounting bolts something secure to thread into.

  • Fits Groco 3/4" and 1" flanged seacocks (FBV-750, FBV-1000) and flanged adapters (IBVF-750, IBVF-1000)
  • Diameter: 4.29"
  • Insert threads: 5/16"-18
  • 1/2" thick: rigid enough for a secure installation, flexible enough to follow minor hull curvature
  • Marine-grade PVC foam that won't swell or absorb moisture
  • Threaded inserts press into the hull side of the block to match the seacock flange holes
  • Groco part number: BB-1

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