Home / Spare Parts / Tanker Spares / 2 1/2″ Fort Vale 2 BSP Super Maxi MK3 Relief Valve Stainless Steel2 1/2″ Fort Vale 2 BSP Super Maxi MK3 Relief Valve Stainless Steel Request a Quote Home / Spare Parts / Tanker Spares / 2 1/2″ Fort Vale 2 BSP Super Maxi MK3 Relief Valve Stainless Steel2 1/2″ Fort Vale 2 BSP Super Maxi MK3 Relief Valve Stainless Steel Request a Quote Product Code - FV010/10506 Fort Vale 2.5" BSP Super Maxi MK3 Relief Valve Stainless Steel.