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Polished, chrome-plated finish easily wipes clean and is highly resistant to corrosion. Extra-large die-stamped size markings are easy to read and can’t wear off. Four detent grooves provide a secure connection with the drive tool.

Black phosphating - A fine and dense coating brings more corrosion and wear resistance for longtime use.

11 in. Socket well Depth: 099 in. Deep-length sockets reach into wells and accommodate the excess threads of longer shafts. Polished, chrome-plated finish easily wipes clean and is highly resistant to corrosion.

1. Craftsman
#ad
Metric, 3/8-Inch Drive, 6-Point CMMT43584, 21mm, CRAFTSMAN Shallow Socket
#adCraftsman #ad - Increased torque: metric Sockets Feature 6 Point Socket with Fastener. Corrosion resistance: The Shallow Socket Has Full Polish Chrome Finish.More information #ad
Full lifetime warranty, refer to "Warranty & Support" section below for full details. Quick size identification: Large Markings. Meets or exceeds ASME Specifications.Brand | Craftsman #ad |
Manufacturer | CRAFTSMAN #ad |
Part Number | CMMT43584 |
Model | CMMT43584 |
More information #ad
2. Craftsman
#ad
CRAFTSMAN Deep Socket, 6-Point CMMT99144, 21mm, Metric, 3/8-Inch Drive
#adCraftsman #ad - Meets or exceeds ASME Specifications. Quick size identification: Large Markings. Full lifetime warranty, refer to "Warranty & Support" section below for full details.More information #ad
Increased torque: 6-point metric socket comes with fastener. Corrosion resistance: Deep socket comes with full polish chrome finish. Increased accessibility: Deep socket.Brand | Craftsman #ad |
Manufacturer | CRAFTSMAN #ad |
Part Number | CMMT99144 |
Model | CMMT99144 |
More information #ad
3. Sunex Tools
#ad
Sunex 321md 3/8-Inch Drive 21-Mm Deep Impact Socket
#adSunex Tools #ad - The design drives the side of the fastener instead of the corner. 3/8-inch drive. Forged from the finest chrome molybdenum alloy steel-the best choice for strength and durability. Radius corner design - to extend the life of fasteners. 21mm deep impact socket.More information #ad
Brand | Sunex Tools #ad |
Manufacturer | Sunex International #ad |
Height | 2.5 Inches |
Length | 0.9 Inches |
Weight | 0.38 Pounds |
Width | 0.9 Inches |
Part Number | 321MD |
Model | 321MD |
More information #ad
4. Sunex Tools
#ad
Sunex 321m 3/8-Inch Drive 21-Mm Impact Socket
#adSunex Tools #ad - Radius corner design - to extend the life of fasteners. 3/8-inch drive. The design drives the side of the fastener instead of the corner. Forged from the finest chrome molybdenum alloy steel-the best choice for strength and durability. 21mm impact socket.More information #ad
Brand | Sunex Tools #ad |
Manufacturer | Sunex International #ad |
Height | 1.2 Inches |
Length | 0.9 Inches |
Weight | 0.03 Pounds |
Width | 0.9 Inches |
Part Number | 321M |
Model | 321M |
More information #ad
5. TEKTON
#ad
TEKTON 3/8 Inch Drive x 21 mm Deep 6-Point Socket | SHD13121
#adTEKTON #ad - 6-point socket opening provides an ideal, exact fit for hex-shaped fastener heads. Beveled inner rim of the socket opening helps guide it smoothly onto fasteners.Polished, chrome-plated finish easily wipes clean and is highly resistant to corrosion. Extra-large die-stamped size markings are easy to read and can’t wear off. Four detent grooves provide a secure connection with the drive tool.
More information #ad
Overall socket length: 2. 49 in. Socket end diameter: 1. 11 in. Drive end Diameter: 1. 11 in. Socket well Depth: 099 in. Deep-length sockets reach into wells and accommodate the excess threads of longer shafts. Socket geometry is designed to apply force to flat sides of fasteners and not the corners, preventing round-off.Brand | TEKTON #ad |
Manufacturer | TEKTON #ad |
Height | 1.2 Inches |
Length | 2.5 Inches |
Weight | 0.4 Pounds |
Width | 1.2 Inches |
Part Number | SHD13121 |
Model | SHD13121 |
Warranty | No time limits, no receipts: tekton.com/tool-help |
More information #ad
6. Jetech
#ad
Heat-Treated Chrome Molybdenum Alloy Steel, Metric, Jetech 3/8-Inch Drive 21mm Deep Impact Socket with 6-Point Design
#adJetech #ad - Radius corner design - the lifespan of both the fastener and socket will be greatly prolonged with the force distributed to the inwall. Cr-mo alloy steel - cr-mo deep impact socket features with added strength, higher working temperatures and corrosion resistance.Black phosphating - A fine and dense coating brings more corrosion and wear resistance for longtime use.
More information #ad
It's much stronger to stand greater impact force than chrome vanadium ones. Cold forging & heat treatment - Cold forging and heat treatment greatly improve the performance of the socket with enhanced hardness, increased wear-resistance and lifespan. Extra depth - provide more space to accommodate longer bolts and wider applications to facilitate your work.Brand | Jetech #ad |
Manufacturer | Jetech #ad |
Part Number | FK3ov8-D21 |
More information #ad
7. TEKTON
#ad
TEKTON 3/8 Inch Drive x 21 mm Deep 12-Point Socket | SHD13321
#adTEKTON #ad - Extra-large die-stamped size markings are easy to read and can’t wear off. Overall socket length: 2. 49 in. Drive end diameter: 1. 11 in. Socket end Diameter: 1.11 in. Socket well Depth: 099 in. Deep-length sockets reach into wells and accommodate the excess threads of longer shafts. Polished, chrome-plated finish easily wipes clean and is highly resistant to corrosion.
More information #ad
Beveled inner rim of the socket opening helps guide it smoothly onto fasteners. Four detent grooves provide a secure connection with the drive tool. Socket geometry is designed to apply force to flat sides of fasteners and not the corners, preventing round-off. 12-point opening fits double hex 12-sided, hex, and square-shaped fasteners.Brand | TEKTON #ad |
Manufacturer | TEKTON #ad |
Height | 1.2 Inches |
Length | 2.5 Inches |
Width | 1.2 Inches |
Part Number | SHD13321 |
Model | SHD13321 |
Warranty | No time limits, no receipts: tekton.com/tool-help |
More information #ad
8. Performance Tool
#ad
Performance Tool W38221 6-Point Socket, 21mm, 3/8" Drive
#adPerformance Tool #ad - Polished nickel chrome plated finish resists corrosion. Recessed edges. Socket openings are designed to reduce fastener rounding. Chrome vanadium alloy steel construction for strength and durability. Large stamping for quick identification.More information #ad
Brand | Performance Tool #ad |
Manufacturer | Wilmar #ad |
Height | 0.9 Inches |
Length | 3.6 Inches |
Weight | 0.02 Pounds |
Width | 1.6 Inches |
Part Number | W38221 |
Model | W38221 |
Warranty | Lifetime |
More information #ad