Parker found that adding a beavertail forend required a design change to the forend loop used to hold the forend to the barrels.  The larger beavertail forend put enough added pressure on the hooking loop found under the barrel that the solder would fail.  To resolve this problem they increased the solder area, reinforcing the loop.  See the picture below and note the larger loop connection.

Also, without the reinforced loop, the finger latch on the forend will be recessed lower into the beavertail wood because of its added thickness.  If it is a factory installed beavertail forend, the reinforced loop will allow the latch to be flush with the thicker beavertail forend wood.  A Parker factory installed beavertail forend finger latch will fit much like it is on standard Parker splinter forends.

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