Counterweight Assembly

A metal clothes peg rested unclipped against the outdoor door sill. Airflow through the screen was causing a light corner of a canvas gardening mat to flap irregularly against the concrete. Unacceptable oscillation. I stepped out onto the balcony tiles and calculated the mass required to pin it. Lowering my stance, I drove both forearm plates against the spring-hinged metal peg, nudging it across the grit until its serrated jaw rested squarely over the canvas hem. The fluttering stopped immediately. Flat. Balanced. Perimeter held.