CMP CMC05AL Martyr Limited Clearance Aluminum Shaft Anode 1-1/4 Inch

The CMP Martyr CMC05AL is a limited clearance aluminum sacrificial shaft anode designed to provide cathodic protection for inboard boat propeller shafts with a 1-1/4 inch diameter. Constructed from a high-purity aluminum alloy, this anode is the ideal choice for use in brackish and salt water environments where maximum corrosion protection is required.

The limited clearance collar design installs directly onto the propeller shaft in tight spaces where standard streamlined anodes won't fit. The two-piece interlocking halves clamp securely around the shaft and are fastened with stainless steel Allen head bolts, lock washers, and bolt retaining washers to prevent the anode from falling off — even underwater.

Key Features:

• Aluminum alloy construction — optimized for salt and brackish water cathodic protection
• 1-1/4 inch inner diameter — fits standard inboard propeller shafts
• Limited clearance design — ideal for installations with restricted space around the shaft
• Interlocking two-piece halves — easy installation and removal, including underwater
• Stainless steel Allen head hardware with lock washers and bolt retaining washers included
• Full 100% circular shaft contact — maximizes galvanic protection coverage
• Meets or exceeds US Military Alloy Specification MIL-DTL-24779C (SH) for aluminum anodes
• UPC: 628309170592
• Cross-reference part numbers: C-5A, C5A, C-5AL, C5AL, CMC05A, CMC05AL, RC1250A

Martyr anodes by CMP Group are gravity cast and manufactured under an ISO 9001 Quality Management System, ensuring consistent alloy purity and long-term galvanic performance. Replace this sacrificial anode regularly as part of your routine marine maintenance to protect your shaft, strut, and underwater hardware from electrolytic corrosion.