This is a single new/old-stock Ludwig P80 piccolo snare drum throw-off. Three lengths of mounting screws included (only the longest is shown in the stock photo.) 1" mounting hole spacing.
This a slightly older yet unused one I have in my stock, but I only have one of these left at this price. Ludwig has steadily raised the price on these over the past decade to a ridiculously high amount (generally around $150 right now) so this is likely your last chance to get one for under $100!