Feliway Optimum Sale! from £26.99 Size Starter Pack: Diffuser + 1 x 48ml Refill 48ml Refill: Single 48ml Refill: Pack 3 Qty. Add to Cart This item is currently on backorder but you can still purchase it now and we'll ship as soon as more become available. Feliway Optimum is the most advanced Feliway solution to help solve the common signs of stress in cats: Scratching, Urine spraying, Tension and Conflict between cats, Hiding, Reactions to changes. How to use: Plug the diffuser into an electrical socket. For the best calming effect, leave the diffuser switched on 24/7. Replace the refill every 30 days as needed. Each diffuser refill covers an area of 70m² Avoid plugging in the diffuser under shelves, behind doors, curtains or furniture, as it will not work properly. SKU: CEFEL22 Tweet