Warne Maxima Permanent Attach Ring, 30mm, Low, Matte Finish 213M The Maxima Fixed Ring Series fit Weaver style cross slot bases and incorporate a Warne square stainless steel recoil control key in both the front and rear rings. This ensures a no slip positive recoil surface across the entire slot of the base and is capable of withstanding the heaviest of recoil. The Maxima square recoil key also protects against swaging or peening of the bases when used on softer or less durable materials. The Maxima Fixed Ring band is also substantially wider for additional clamping surface around the scope to hold the optic firmly in place.