Are these ornaments shatterproof?

Yes. They are made of plastic rather than glass, so they resist breaking when dropped or knocked off the tree.

How big is each ornament?

Each ball is 2.75 inches in diameter, a mid-size ornament that works on most trees.

20 per box, in a mix of four finishes.

The set is described as a four-finish assortment, so the balls vary in surface treatment within the same black color.

The product information does not list hooks or hanging hardware, so plan on using your own.

They blend into a dark green or black tree. They stand out best against flocked, white or brightly lit trees.

At BulbAmerica, for $52.99, as of our latest check.

$52.99at BulbAmericaChecked Nov 10

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