Matala Hakko Air Diffusers with Included Base Diffuser Type:MDB22 (Large Base / Two 9" Diffusers) Features 3/4" FPT threads in

Features 3/4" FPT threads in both ends

Built-in pressure relief valve protects the pump if airlines become kinked

Great for retaining walls or pond-free applications

Ammonia-Away removes deadly ammonia

Matala Hakko Air Diffusers with Included Base Diffuser Type:MDB22 (Large Base / Two 9" Diffusers) Features 3/4" FPT threads inMatala Hakko Base Air Diffusers are membrane air diffuser assemblies that feature heavy duty plastic bases with soft edges. These bases are hollow so that they can be filled with sand or gravel, eliminating the need for bricks and straps to get the diffuser to sink. Two sizes of bases are offered: the small base can accommodate one or two diffusers, and the large base can accommodate two or four diffusers. Heavy duty diffusers produce medium bubbles,