Greenlee 73BB Round Standard K...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$136.86
Greenlee 73BB Round Standard Knockout Punch Set, Mild Steel

Greenlee 73BB Round Standard Knockout Punch Set, Mild Steel

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Model: 73BB

In Stock (leaves warehouse same day if ordered before 3pm ET)

$136.86
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Greenlee 73BB Round Standard Knockout Punch Set

The Greenlee 73BB Round Standard Knockout Punch Set is a complete punch unit consisting of a punch, die, and draw stud, engineered to create clean, fast, and accurate round holes in electrical enclosures and panels. This family is available in sizes ranging from 1-1/2" up to 1-15/16" (34.600 MM), giving electricians and panel fabricators a selectable round knockout size to match the connector or conduit fitting required on the job. Every size in the 73BB lineup is rated for a capacity of 10 GA (3.500 MM) in mild steel and is built for use with battery-powered, hydraulic, ratchet, or manual drivers. When properly assembled through pilot holes, the Greenlee 73BB delivers consistent, professional-grade results across its full size range.

Key Features

  • Selectable Round Sizes: Choose from sizes spanning 1-1/2" through 1-15/16" (34.600 MM), covering common conduit and connector openings used in panel and enclosure work.
  • Complete Punch Unit: Each size includes a punch, die, and draw stud for a ready-to-use knockout solution, eliminating the need to source components separately.
  • Standard Round Knockout Type: Engineered to produce round holes that accept common conduit and connector fittings in electrical panels and enclosures.
  • Mild Steel Capacity: Rated for 10 GA (3.500 MM) mild steel across the family, giving installers confidence when punching through standard enclosure and panel material.
  • Versatile Driver Compatibility: Works with battery-powered, hydraulic, ratchet, or manual drivers, making it adaptable to whatever driver setup is already on the job or in the truck.
  • Alignment Markings: Integrated alignment markings improve punching accuracy and productivity, helping installers make precise holes on the first attempt.
  • Clear Part Identification: Punches and dies are marked with catalog numbers and sizes for quick identification, reducing downtime when matching components in the field.
  • Pilot Hole Assembly: When properly assembled through pilot holes, the unit produces clean, fast, and accurate holes with minimal burring or deformation.

Technical Specifications

  • Includes: Punch, Die And Draw Stud
  • Type: Standard Round Knockout
  • Capacity Mild Steel: 10 GA (3.500 MM)
  • Available Sizes: 1-1/2", 1-15/16", 34.600 MM

Typical Applications

  • Electrical Panel and Enclosure Fabrication
  • Conduit and Connector Knockout Installation
  • Commercial and Industrial Electrical Installations
  • Panelboard and Load Center Modifications
  • Field Retrofit and Renovation Work

Why Greenlee?

Greenlee's 73BB knockout punch set is built as a complete, precision-marked assembly so electricians and panel builders can rely on clean, accurate holes every time, regardless of which size in the range is selected. With clear catalog and size markings, alignment features, and compatibility across multiple driver types, the Greenlee 73BB family is designed to keep professionals productive and precise on demanding electrical installation and fabrication jobs.

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Manufacturer Resources

Product Specs

Product Type:
Knockout Set
Configuration:
Round Standard Knockout
Department:
Electrical
Product Subgroup:
Knockout Punches
list_batch:
GREE-20260923
Product Material:
Mild Steel
Series:
73BB
Product Group:
Electrical Installation Tools

Greenlee 73BB – Frequently Asked Questions

1) What size holes does the Greenlee 73BB knockout punch set make?
The 73BB family covers round knockouts from 1-1/2 inches up to 1-15/16 inches, with a 34.6 mm metric size in between. Three orderable sizes: 1-1/2 inch (cat. 737BB), 34.6 mm (cat. 73BB), and 1-15/16 inch (cat. 75BB). Pick the size by the connector or conduit fitting going into the opening, not by the conduit trade size alone.
2) How thick a panel will a Greenlee 73BB punch go through?
Every size in the 73BB range is rated to 10 GA (3.5 mm) in mild steel. That covers typical electrical enclosure and panelboard sheet. Stainless, aluminum plate, or anything heavier than 10 gauge mild steel is outside the rating on this punch.
3) Can I use the Greenlee 73BB punch with a battery hydraulic driver, or is it manual only?
Both. The 73BB works with battery-powered and hydraulic drivers as well as ratchet and manual setups, so you are not locked into one tool. The draw stud supplied with the unit is what ties it to the driver, and the punch must be assembled through a pilot hole before drawing it up.
4) Is the Greenlee 73BB a round punch or a square/conduit-shaped one?
Round, standard knockout. It produces a plain round hole sized to take common conduit and connector fittings in panels and enclosures. If you need a square, D-shaped, or oversized conduit knockout, a standard round punch like this is the wrong tool.
5) Which Greenlee 73BB part number do I order for a 34.6 mm metric knockout?
Catalog number 73BB is the 34.6 mm size. The 1-1/2 inch is 737BB and the 1-15/16 inch is 75BB. Punches and dies are stamped with the catalog number and size, so once they are loose in the case you can still match components without guessing.
6) How do I get a clean hole without the panel deforming when punching an enclosure?
Drill the pilot hole first and assemble the 73BB punch, die, and draw stud through it before drawing up. Used that way it gives a clean hole with minimal burring or deformation. The alignment markings on the punch body are there to let you line up on your layout mark the first time rather than re-punching.
How fast can I get the Greenlee 73BB delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Greenlee 73BB come with a warranty?
Absolutely. The Greenlee 73BB is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Greenlee 73BB?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the Greenlee 73BB from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support, and rewards on every order. Our team is always ready to help you choose the right product for your project.
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