I found these instructions, url looks shady but it's legit:
https://cdn.shopify.com/s/files/1/0649/1897/files/COASFST16T_Customer_Copy.pdf?6206060808085959914
It does require oil: "Once the filter is dry, re-oil with ITG JDR-2 dust retention coating. If this is not available, only use a specific foam air filter oil. Suitable brands that we are aware of include Silkolene and Rock Oil. If foam air filters are used in a ‘dry’ or non-oiled state, they still provide filtration of larger dust particles, and they will also retain most smaller dust particles due to an electrostatic effect. Electrostatic dust retention is much less reliable than oil retention, so if a filter is used without oil, it is very important to monitor whether any dust is passing through the filter, and to clean the filter frequently. Some dust, which can potentially damage the engine, may pass through a filter used in dry condition.
ITG will not provide any warranty when a filter is used in dry condition, or has not been maintained according to instructions.