These mats are used in conjuntion with the EVO Repel.Insert them into the system to provide up to 10 nights of protection, (4-6 hours per night). Experience maximum defence in under a minute.250mg D-Allethrin, twice the small mats.Size 3.45 x 4.35 x 0.28cm. Compatible with Thermacell. THERE IS 10 IN A PACK.