Plastia (https://www.plastia.eu/en/)
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The growing cover with adjustable ventilation. This practical gadget will protect your seedlings from frost and fluctuating weather. Developed for combining with Berberis large-volume self-watering planters, it is an accessory that belongs in every home. Attach the cover to the planter with the 2 clamps during strong rain or wind. Storage is easy, just put growing cover into the selfwatering insert. Packege includes: 1x growing cover, 1x slider, 2x clips