The Bug 3+ Action Kit for GoPro HERO3+/HERO4 from LEE Filters contains a Blue Water filter, a Green Water filter, and a special frame that fits the HERO3+/HERO4 housing. The included filter holder works with other filters in the LEE Bug series as well, and is designed specifically to fit the lens port of the HERO3+/HERO4 housing. If you use a HERO3 housing, there is a different kit that includes the appropriate filter holder.
LEE Bug Filter Holder Blue Water Filter Green Water Filter Protective Pouch Cleaning Cloth
LEE Filters Bug 3+ Underwater Kit for GoPro HERO3+/HERO4