Standard Abrasives 703654, A/O Square Pad, 2 in x 2 in x 1/2 in, 1/4-20, 80, 7100105433 
Insize 4701-1, ADJUSTABLE SQUARE, 6928640318351
$152.50
The straight edge can move and can be locked by the clamping screw.
Made of hardened stainless steel.
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