120mm Self-Stick Insulation Pins - 30 Sets, 1.5" Locking Washers for Foam Board,

Pin Length: 120mm (4.72"). Secure Tight: Fasten with self-locking washers (1 nail per corner for maximum stability) and bend or snip excess nail for a tight, long-lasting hold. Self Locking Washers Size: 38mm (1.5").

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