Mast Ring 4mm $7.54 BF0531 Package of 10 4mm. Mast Ring 4mm quantity Add to cart SKU: BF0531 Category: Above Deck Tags: mast fitting, mast ring, ring Description Additional information Brand Attachment Description Package of 10 brass finished rings. 4mm. Helpful Tools: Marking & Measuring Tools Tweezers and Pick-up Tools Magnifying tools & headlamps LC1764 LED Headband Magnifier w/4 Lenses Additional information Weight 0.09 lbs Dimensions 10 × 8 × 2 in Brand Billing Boats Kits