Bare Magnesium Anodes
Magnesium bare anode is usually made into two types with different electro-potential (relative to Cu/CuSO4 reference electrode):
- High Potential (HP) magnesium anode (-1.70V)
- Standard Potential (H-1) magnesium anode (-1.50V)
Element | Grade ASTM B843 – M1C | Grade ASTM B843 – AZ63B |
High Potential (HP 1.7V) | Standard Potential (H-1 1.5V) | |
Aluminum | 0.01% Max. | 5.3 – 6.7% |
Zinc | — | 2.5 – 3.5% |
Manganese | 0.50 – 1.30% | 0.15 – 0.70% |
Silicon | 0.05% Max. | 0.10% Max. |
Copper | 0.02% Max. | 0.02% Max. |
Nickel | 0.001% Max. | 0.002% Max. |
Iron | 0.03% Max. | 0.003% Max. |
Other Each | 0.05% Max. | — |
Others Total | 0.30% Max. | 0.30% Max. |
Magnesium | Remainder | Remainder |
Magnesium anodes are used predominately onshore in relatively high resistivity soil and water.
Alloy Standard | Open Circuit Potential (-V) | Close Circuit Potential (-V) | Current Capacity (Min.) | Current Efficiency |
ASTM B843 – M1C | 1.70 – 1.75 | 1.70 – 1.75 | 500A.h/lbs (1100A.h/kg) | 50% Min. |
ASTM B843 – AZ63B | 1.50 – 1.55 | 1.70 – 1.75 | 550A.h/lbs (1230A.h/kg) | 55% Min. |

We offer three types of standard magnesium anodes: D type, R type and S type.
D Type
Anode Model | Anode Weight | High Potential (HP, 1.7V) | Standard Potential (H-1, 1.5V) | ||||||||
Length | Width | Height | Length | Width | Height | ||||||
JA – MG – 5D2 | 5lbs (2.3kg) | 7.5″ (190mm) | 3.5″ (89mm) | 3.7″ (95mm) | 12″ (305mm) | 3.5″ (89mm) | 3.7″ (95mm) | ||||
JA – MG – 9D3 | 9lbs (4.1kg) | 13.6″ (345mm) | 3.5″ (89mm) | 3.7″ (95mm) | 12.8″ (325mm) | 3.5″ (89mm) | 3.7″ (95mm) | ||||
JA – MG – 17D3 | 17lbs (7.7kg) | 25.25″ (645mm) | 3.5″ (89mm) | 3.7″ (95mm) | 24″ (610mm) | 2.5″ (63.5mm) | 2.6″ (67mm) | ||||
JA – MG – 20D2 | 20lbs (9.1kg) | 60.0″ (1250mm) | 2.75″ (70mm) | 3.0″ (76mm) | 58.5″ (1485mm) | 2.75″ (70mm) | 3.0″ (76mm) | ||||
JA – MG – 32D5 | 32lbs (14.5kg) | 19.6″ (498mm) | 5.5″ (140mm) | 5.7″ (146mm) | 18.6″ (472mm) | 5.5″ (140mm) | 5.7″ (146mm) | ||||
JA – MG – 48D5 | 48lbs (21.8kg) | 29.5″ (750mm) | 5.5″ (140mm) | 5.7″ (146mm) | 28.0″ (710mm) | 5.5″ (140mm) | 5.7″ (146mm) | ||||
JA – MG – 60D4 | 60lbs (27.3kg) | 60.0″ (1524mm) | 4.4″ (112mm) | 4.4″ (112mm) | 58.5″ (1485mm) | 4.4″ (112mm) | 4.4” (112mm) |
S Type
Anode Model | Anode Weight | High Potential (HP, 1.7V) | Standard Potential (H-1, 1.5V) | ||||||||
Length | Width | Height | Length | Width | Height | ||||||
JA – MG – 17S3 | 17lbs (7.7kg) | 26.8” (680mm) | 3.4” (86.25mm) | 3.0” (76mm) | 25.6” (650mm) | 3.4” (86.25mm) | 3.0” (76mm) | ||||
JA – MG – 32S5 | 32lbs (14.5kg) | 22.2” (563mm) | 4.6” (117mm) | 5.0” (127mm) | 21.0” (535mm) | 4.6” (117mm) | 5.0” (127mm) | ||||
JA – MG – 48S5 | 48lbs (21.8kg) | 33.3” (845mm) | 4.6” (117mm) | 5.0” (127mm) | 32.3” (820mm) | 4.6” (117mm) | 5.0” (127mm) | ||||
JA – MG – 60S4 | 60lbs (27.3kg) | 60” (1520mm) | 4.0” (102mm) | 4.0” (102mm) | 58.4” (1485mm) | 4.0” (102mm) | 4.0” (102mm) |
R Type
Anode Model | Anode Weight | High Potential (HP, 1.7V) | Standard Potential (H-1, 1.5V) | ||||
Diameter | Length | Diameter | Length | ||||
JA – MG – 1R8 | 1lbs (0.45kg) | 1.65” (42mm) | 8.3” (210mm) | 1.65” (42mm) | 8.0” (205mm) | ||
JA – MG – 17R | 17lbs (7.7kg) | 4.5” (114mm) | 17.3” (440mm) | 4.5” (114mm) | 16.1” (410mm) | ||
JA – MG – 32R | 32lbs (14.5kg) | 5.75” (146mm) | 19.7” (505mm) | 5.75” (114mm) | 18.5” (470mm) | ||
JA – MG – 50R | 50lbs (22.7kg) | 7.0” (178mm) | 19.9″ (505mm) | 7.0″ (178mm) | 19.3″ (490mm) | ||
JA – MG – 60R | 60lbs (27.3kg) | 4.5” (114mm) | 60.0” (1524mm) | 4.5” (114mm) | 57.0” (1450mm) |
All weights and dimensions are nominal and subject to variation in material compositions and Jennings Anodes foundry tolerance.
Above standard sizes are available at Jennings Anodes warehouse. Other configurations are available upon special request.
We employ rigorous internal and industry testing standards to ensure optimum quality and superior performance and lifespan of our magnesium anodes. Third party testing is available upon request.
Each anode is stamped or labelled with a unique serial number for quality tracking and ensuring full product traceability.
Testing | Chemical Composition | Electrochemical Properties | Physical Properties & Appearance | ||
Standard | ISO 9001 Quality Management System and Foundry Internal Quality Standard | ||||
ATSM A518 Gr1 | ATSM A518 Gr3 | Foundry ITP | |||
Testing Item | Chemical Analysis | Circuit Potential, Current Efficiency | Change to Surface Inspection, clean free from cracks, shrinkage or inclusions. Physical Dimensions & Weight as per Anode Specification. Steel Core / Anode Resistance | ||
Equipment & Devices | Optical Emission Spectrometer OBLF QSN 750 | Electrochemical Analyzer EPI 200 | Calibrated digital measuring devices |
We have strict packing protocols to guarantee safe delivery of our products. Clear shipping marks and documentation make delivery acceptance straightforward and simple.
Custom packing is available upon request.
Shipping Documents:
- Proforma invoice
- Packing list
- Testing reports (Chemical Composition, Electrochemical Properties Test, Certificate of Compliance)
- Others upon request (e.g. Certificate of Origin)
Anode Model | Unit of Measurement | Packing Details | ||||||||
Number of Anodes per Crate/Pallet | Crate/Pallet Dimension | Net Weight | Gross Weight | Number of Crates/Pallets per 20ft. Container | ||||||
JA – MG – 5D3 | EA | 270 | 40″ × 40″ × 27″ (1020 × 1020 × 690mm) | 1370lbs (622kg) | 1410lbs (635kg) | 33 | ||||
JA – MG – 9D3 | 270 | 41.5″ × 41.5″ × 32″ (1050 × 1050 × 810mm) | 2440lbs (1108kg) | 2478lbs (1125kg) | 19 | |||||
JA – MG -17D3 | 144 | 41.5″ × 41.5″ × 32″ (1050 × 1050 × 810mm) | 2478lbs (1108kg) | 2522lbs (1125kg) | 18 | |||||
JA – MG – 20D2 | 120 | 57″ × 32.5″ × 32″ (1450 × 810 × 800mm) | 2406lbs (1092kg) | 2456lbs (1110kg) | 19 | |||||
JA – MG – 32D5 | 80 | 41.5″ × 41.5″ × 33.5″ (1050 × 1050 × 860mm) | 2560lbs (1160kg) | 2600lbs (1180kg) | 18 | |||||
JA – MG – 40D3 | 60 | 58″ × 35.5″ × 26.5″ (1470 × 910 × 680mm) | 2406lbs (1092kg) | 2456lbs (1115kg) | 19 | |||||
JA – MG – 48D5 | 50 | 41.5″ × 41.5″ × 34″ (1050 × 1050 × 870mm) | 2405lbs (1090kg) | 2450lbs (1112kg) | 19 | |||||
JA – MG – 50R8 | 50 | 43″ × 35″ × 42.5″ (1100 × 900 × 1080mm) | 2500lbs (1135kg) | 2545lbs (1155kg) | 18 | |||||
JA – MG – 60S4 | 40 | 61.5″ × 40″ ×25.5″ (1560 × 1020 × 650mm) | 2405lbs (1092kg) | 2460lbs (1116kg) | 19 | |||||
JA – MG – 60D4 | 40 | 60.5″ × 32.5″ × 28.5″ (1540 × 810 × 710mm) | 2405lbs (1092kg) | 2460lbs (1116kg) | 19 |

More about bare magnesium anodes
Our bare magnesium anodes are available in a range of designs which are specifically crafted to offer different conductive properties and connection options to suit particular types of structures.
Hull anodes are designed to flush mount against the hulls of ships, dams, or tanks via built in steel straps, whereas drive-in anodes are designed to be driven into the ground to protect buried propane tanks or steel pylons.
We have been widely recognised by a number of industries for manufacturing and supplying high quality and efficient anodes.