How much does this cost to the nearest dollar?

Nispira Charcoal Water Filter Replacement Compatible with Drinkwell Pet Fountain Model Original, Platinum, Big Dog, Multi-Tier, Outdoor Dog, Mini, Everflow, Zen - Size 5.5 x 3.25 x 0.25 (12 Packs) (NOT FOR OTHER BRANDS/ MODELS))
12 Packs 2 chambers charcoal water filter compatible with Drinkwell pet fountain only. Compatible models are ORIGINAL, PLATIUM, BIG BOG, MULTI-TIER, INDOOR/OUTDOOR, MINI, EVERFLOW and ZEN. Food grade activated carbon water filter removes bad tastes and odors from water, keeping it fresh; change every 2-4 weeks to maintain water freshness. Nispira branded filters contain 50% more carbon

Price is $16.00

Price: $15.99