In stock
Grouped product items
Product Name Price Qty
1/4"- 20 Threaded Brass Inserts (8 per Pack)
1/4"- 20 Threaded Brass Inserts (8 per Pack) Item #: 33183
Oversold Until 10/18/2018
5/16" -18 Threaded Brass Inserts (8 per Pack)
5/16" -18 Threaded Brass Inserts (8 per Pack) Item #: 33191
Temporarily Oversold
3/8" - 16 Threaded Brass Inserts (8 per Pack)
3/8" - 16 Threaded Brass Inserts (8 per Pack) Item #: 71589
Temporarily Oversold

Threaded Brass Inserts - Select size

Item #
90% of 100
Threaded Brass Inserts - Select size
Threaded Brass Inserts - Select size

Threaded brass inserts guaranteed not to rust. Made from solid brass. Size listed is the size of the internal machine threads. Sold in packs of 8. Can be installed with screwdriver, threaded insert wrench (sold separately) or threaded insert power drive (sold separately).

Solid brass threaded insert is easy to install. Drill a hole the same size as body insert. Diameter permits the use of machine screws and bolts instead of wood screws. Drive with 3/8" x 3/64" flatblade screwdriver or with threaded insert wrench (#48629). For additional strength, install with epoxy glue. Brass inserts have different external dimensions as the steel inserts with the same internal thread size

(1) 8-Pack of Threaded Brass Inserts
More Information
Brand No
Manufacturer Part Number No
Weight 1.0000
Tech Spec

Item #33183- 1/4"- 20 Threaded Brass Inserts:

  • Pilot Hole: 3/8'' Wide
  • Width with threads: 15/32''
  • Thread Height: 5/16''
  • Overall Height: 1/2''

Item #33191- 5/16" -18 Threaded Brass Inserts:

  • Pilot Hole: 1/2'' Wide
  • Width with threads: 19/32''
  • Thread Height: 3/8''
  • Overall Height: 5/8''

Item #71589 - 3/8" - 16 Threaded Brass Inserts:

  • Width with threads: 19/32''
  • Overall Height: 5/8''
  • Technical Documents
    Prop 65 WarningWARNING: Cancer & Reproductive Harm -

    Prop 65 WarningWARNING: Drilling, sawing, sanding or machining wood products can expose you to wood dust, a substance known to the State of California to cause cancer. Avoid inhaling wood dust or use a dust mask or other safeguards for personal protection. For more information go to
    4.5 / 5.0
    36 Reviews
    5 Stars
    4 Stars
    3 Stars
    2 Stars
    1 Star
    Brass works better than steel
    I have used both brass and steel inserts. I have found that the brass ones are much easier to install. They don't tend to go sideways as the steel ones sometimes do.
    May 18, 2018
    over 4 years ago
    Woodworking Experience:
    Great for jigs
    I installed these 1/4-20 inserts in MDF using a length of all-thread and a second nut (jam nut) to secure the insert to the all-thread. I drilled the recommended size hole (on the Rockler package) using a drill press. Then I chucked the all-thread into the drill press and pressed down while turning the jam nut with a wrench. The inserts threaded in perfectly. I have tried using a large screwdriver to install brass inserts and had the slot break out. Using the drill press I get a much cleaner insert because I can thread the slotted end into the hole.
    May 12, 2018
    5 months ago
    Woodworking Experience:
    These threaded inserts work very well, are easy to install, and hold very well. I would strongly recommend these inserts.
    January 2, 2018
    10 months ago
    Woodworking Experience:
    Brass threaded inserts
    Well made inserts. What I expect from rockler
    December 8, 2017
    11 months ago
    Woodworking Experience:
    works good
    easy to use
    October 1, 2017
    1 year ago
    Woodworking Experience:
    threaded inserts
    great product ,have used many times
    August 31, 2017
    1 year ago
    Woodworking Experience:
    Brass Inserts
    These inserts are useful on projects that are frequently being disassembled or where a lot of holding power is needed. The 1/4-20 insert (#33183) has a diameter on the inside of the outer thread of 3/8". For softwoods a 3/8" hole can be used, but for hardwoods, I recommend a 25/64" hole, otherwise it is difficult to drive. Also, the insert tool (#30174) is invaluable because it helps align the insert as it is being driven. Countersinking the hole is helpful to prevent bulging of the wood at the lip of the hole.
    June 14, 2017
    1 year ago
    Woodworking Experience:
    Serves as what I needed for!!
    May 12, 2017
    1 year ago
    Woodworking Experience:
    exactly what I needed
    My daughter owns a small vintage store, and I've learned to do a lot of furniture repair. We had a low credenza that we wanted to put legs on, and a set of legs that were the perfect height-but the hanger bolts were too long for the metal mounting brackets we usually use. Besides that, there was really no good place to attach the brackets. I added a 3/4" board under the front and two sides, which gave me enough thickness to drill holes for these, and mount the legs tightly and flush against the bottom. I really like that you can screw bolts into these from either end, and all the way through them if the bolts are long.
    April 30, 2017
    1 year ago
    Woodworking Experience:
    Threaded Brass inserts
    Perfect pieces for building shop-made jigs allowing for lock-down threaded knobs to secure mating pieces to any jig. These come in various sizes and materials (brass or steel). I always keep some in my storage drawers. They're a versatile and cost effective means of securing pieces for those special jigs needed for any workshop.
    April 22, 2017
    1 year ago
    Woodworking Experience:
    Start typing your question and we'll check if it was already asked and answered. Learn More
    Browse 9 questions Browse 9 questions and 69 answers
    Why did you choose this?
    Rockler Store
    needed for a project
    Brian R on Aug 19, 2018
    my supply is running low
    James S on Aug 15, 2018
    needed for a project
    Brian R on Aug 19, 2018
    Screen door project
    Travis P on Aug 17, 2018
    my supply is running low
    James S on Aug 15, 2018
    Needed these inserts to make tap handles for my beer towers
    NICKLAS P on Jul 13, 2018
    I ran out.
    Russell C on May 26, 2018
    Item needed for my project
    Joseph J on May 19, 2018
    To match the knurled Knobs
    Lynn and Sally J on May 9, 2018
    I am turning my own wooden cabinet knobs from various exotic woods and this method was best suited for installation.
    Jim Smith on Apr 25, 2018
    I hope to use this with my 1" shoulder 3/8" mandrel on my lathe to make bottle stoppers and other kits accepting a 3/8" thread.
    garrett g on Mar 24, 2018
    That's what I wanted
    Paul M on Jan 14, 2018
    For a project I'm working on
    Peter P on Nov 24, 2017
    Using these to mount tactical flashlights on a church parade float.
    William B on Nov 19, 2017
    These work great. If in your budget, get the drivers as well.
    Larry U on Nov 2, 2017
    Needed for construction of my bottle stopper lazy-susan w/3/8" all-thread rod.
    Jim S on Sep 29, 2017
    have used these before and was very satisfied
    PATRICIA L on Aug 10, 2017
    Plan requirement
    JACK M on Jul 16, 2017
    better for project
    Harold a on Jul 8, 2017
    needed for project
    Chester G on Jun 28, 2017
    needed for use with brass knob
    Neil Ernest S on May 18, 2017
    The screws for this insert provide a nice clean fit.
    Jim Smith on May 10, 2017
    Because I have used them in the past and they are a great product.
    RON W on Apr 27, 2017
    connect two pieces of wood!!
    PERRY S on Apr 17, 2017
    I've used brass inserts previously and know what is required to install them correctly.
    Roger L on Apr 4, 2017
    had to bolt things together
    Robert B on Mar 22, 2017
    Had run out of this size.
    Russell H on Mar 21, 2017
    The truth is this is the best value for my buck. No one had a better deal. Now if they perform as expected, I will be back
    RON B on Feb 28, 2017
    Did not receive this item.
    Anthony V on Feb 24, 2017
    Shop tool project
    Nick S on Jan 13, 2017
    Router Table fence construction
    Leon Small BGI 6 on Jan 12, 2017
    Same reason as other things listed above.
    William H on Dec 20, 2016
    needed for lazy susan stand.
    Chris H on Oct 22, 2016
    To mount storm windows in an enclosed porch
    GEORGE D on Oct 18, 2016
    using these with the threaded knobs makes making jigs easy
    Edward K on Oct 16, 2016
    Worked great
    Pete M on Oct 15, 2016
    used them before, can get the quantity I need at one time.
    William C on Oct 11, 2016
    Adding to my supplies for making jigs.
    Hubert on Sep 22, 2016
    I bought this item to be used on 3 cutting gauges that I am building.
    Darrell A on Aug 21, 2016
    Not sure yet but it looks like the threads are finer than the ones you can get from lowes or homedepot. exotic woods that splinter easy will not take construction grade brass inserts with out problems.
    Christopher J on Aug 19, 2016
    Worked perfected
    Gordon B on Jul 29, 2016
    needed them
    Gene R on Jul 11, 2016
    Need for project & used before with good results.
    Mike E on Jun 27, 2016
    Best way to solidly secure metal casters to base of movable wood book shelf units, to handle repeated stress of moving book-laden units for behind-unit cleaning and maintenance.
    Val V on May 21, 2016
    to hold a fence in a kerf saw I am making
    Michael P on May 17, 2016
    Brass inserts will not corrode in an exterior environment
    William H M on May 1, 2016
    Using these for a bottle stopper.
    Mike B on Mar 19, 2016
    Building a delta dovetail jig.
    JOSEPH A on Feb 3, 2016
    Needed for a fixture I an building
    Richard K on Jan 24, 2016
    The shop made sanding station assembly calls for the ¼" inserts. I desired brass to minimize rust as the sanding station will be in an unheated building.
    Marvin J on Jan 24, 2016
    to repair chairs
    ralph c on Jan 3, 2016
    Am trying out a new option for threaded wheels on toy cars!
    Bruce A E on Jan 1, 2016
    Screen door project
    Travis P on Aug 17, 2018
    Needed these inserts to make tap handles for my beer towers
    NICKLAS P on Jul 13, 2018
    what size of pilot hole does one drill for a brass 3/8 inserts ?
    A shopper on Apr 28, 2015
    BEST ANSWER: 1/2" pilot holes are suggested for softwood, 9/16" pilot holes are suggested for hardwoods.
    Just saw a video that says the slotted end should go in first as it's there to help cut the threads and not for a slotted screwdriver. Is that true?
    A shopper on Jun 13, 2015
    Threaded Brass Inserts - Select size
    Threaded Brass Inserts - Select size
    Steel Threaded Inserts - Select size
    Steel Threaded Inserts - Select size
    BEST ANSWER: I would say NO! If the slotted end went in first, How do you screw it in? Also, they sale an installation tool that uses the slot. I made my own tool by using a correct size bolt and a lock nut to secure it to the insert. The use a wrench or nut drive to install the insert.
    What size pilot hole do I drill for the 1/4 20 insert?
    Douglas H on Jul 27, 2017
    BEST ANSWER: Drill the holes for this product (1/4 20 insert) at 29/64 for soft wood and 15/32 for hardwood.
    Make the hole 1/2" deep.
    Will this mandrels threads work with a brass insert for tap handles? I want to drill and mount the inserts first and then turn the tap handle.
    Robmi on Jan 2, 2017
    Threaded Brass Inserts - Select size
    Threaded Brass Inserts - Select size
    Bottle Stopper Mandrel
    Bottle Stopper Mandrel
    BEST ANSWER: As Long as the Internal Thread size of Your insert is 3/8" x 16 (threads per inch) it will Work .
    A 1/2 hole is need for a 5/16-18 insert?
    Eric R on Mar 5, 2017
    BEST ANSWER: If you are going into soft woods then 1/2" bit should work well. For hardwoods or solid surface materials like HDPE plastic I would go to 9/16. I generally found that sizing up a 1/16th for hardwoods and such works well, no matter the insert.
    We are installing a fireplace mantel. I would like to have some threaded inserts at the bottom were permenantly in place. Then during the holidays I can screw in a cup hook or similar to hang stockings. Would this product work for this application? Thank you.
    Julie M on Nov 1, 2015
    BEST ANSWER: when you say cup hooks i'm envisioning the little brass hooks with tapered self threading threads. I'm thinking the swag type hooks used to hang lights, plants etc. would thread into these brass inserts better. hope this helps. I've added pics of the cup hooks but these don't need brass threaded inserts. jim
    Cup Hooks
    Cup Hooks
    Solid Brass Shoulder Hooks
    Solid Brass Shoulder Hooks
    do they have metric wood inserts?
    edward r on Aug 7, 2015
    BEST ANSWER: it doesn't appear that rockler has metric inserts. are they needed to match existing inserts?
    Are these good to use in hardwood to secure metal table legs?
    Robert C on Jan 5, 2017
    BEST ANSWER: Sure. They will work even better in hardwood than softwood. But the pilot hole diameter is more critical. Be sure to follow the manufacturer's recommendation here.
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