Easy to Install Crack Monitoring System for Wall Deformation (2 Pairs)

±1 mm (±0.04") tick marks on X-Y axes; ±0.5 mm (±0.02") discrimination. 2 x monitoring sheet. Supplied with full instructions and Crack Record Sheet & Fix using Screws and Adhesive. Easy to install, waterproof and sunlight resistant wear and scratch resistant.

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