The exterior of the speaker sits flush with your drywall, giving it a sleek and smooth appearance. Once your in-wall speakers are in place, you can connect it to the power and amplification sources to get that rich, deep sound you want in your outdoor space.
Drying oils will change from liquid to a solid film when exposed to oxygen in the air. Nut oils (boiled linseed, tung, etc.) are drying oils, but vegetable (peanut, olive) and mineral oils are non-drying. Edible mineral oil is popular on food contact items, like cutting boards. However, non-drying oils stay wet indefinitely, and they will wash off when the board is scrubbed with soap and water. Because they do not dry to a solid film, non-drying oils are considered a wood treatment, but not a finish.
It can be as much as 3-4 years for an early harvest, high polyphenol containing olive variety which has been filtered then packaged in a well sealed tin or dark bottle then stored in a cool dark place by the grocer and consumer. Best to buy small quantities, use up the oil within 6 months. Any vegetable oil will go rancid with time. The oil is still edible but will taste bad. See our olive oil storage for a more lengthy discussion.