0 My Cart

There are no items in your shopping Cart.

Half Size 3-Ring Binder Mechanisms (Box of 50)


Our mini 3-ring half size binder mechanisms work perfectly with half sheet papers measuring 8 ½" high and 5 ½" wide, featuring 2 ¾" spacing between the rings. Small binder spines are made of durable metal and feature two convenient boosters for easy ring opening, along with holes on each edge to pair with rivets and a rivet setter tool. You can buy half size 3-ring binder mechanisms online for many different purposes; they are popular for church directories, mini scrap books, swatch displays, custom mini ring binders, and much more. Mini binder spine hardware comes in a ring sizes from 1/2" up to 2", with select sizes being available in both round and slant-d shape styles. Mini binder parts are silver in color, and sold in boxes of 50.

Starting at: $52.00
Qty/Pack : 50 Mechanisms

* Required Fields

Capacity Chart

The best way to measure the capacity for a ring binder or ring binder mechanism is to use a stack thickness. To do so, allow your entire stack of paper, tabs, etc. to lay flat, without pressing them down, and measure the height of the stack. We also list an approximate sheet capacity, however, because there are so many different kinds of papers and paper thicknesses, this is a less accurate method of determining capacity. The sheet capacity below is based on standard 20 lb. copy paper alone.

Ring SizeSheet Capacity*Stack Capacity*
1/2" 110 Sheets 1/4" Thick Stack
3/4" 150 Sheets 3/8" Thick Stack
1" 200 Sheets 5/8" Thick Stack
1 ½" 310 Sheets 1" Thick Stack
2" 450 Sheets 1 ½" Thick Stack

Binder Mechanism FAQs

Q: Can I buy smaller than 1 full box?
No. At this time we are only able to sell full boxes of half size binder mechanisms, which contain 50 pieces.


Q: What capacity are the rings?

  Ring Size     Sheet  
  Stack Capacity  
  1/2"     110 Sheets     1/4" Thick
  3/4"     150 Sheets     3/8" Thick 
  1"     200 Sheets     5/8" Thick 
  1 ½"     310 Sheets     1" Thick 
  2"     450 Sheets     1 ½" Thick 


Packaged Quantities

Ring SizeQty / Box
All Sizes 50 pcs

Product Description


If you've been looking for a way to make your own mini ring binders, then you've found the right place. At Binding101 you can buy half size 3-ring binder mechanisms online and use them to make your own custom binders, unique swatches, journals, and so much more! These small ring binder spines are built specifically for a half-sheet of letter size paper, which measures 5 ½" wide and 8 ½" high. This is the exact measurement if you were to pull a regular piece of paper out of your printer and fold it in half, hence the name: half size! 

Packaged in a box of 50 pieces, you can choose ring binder hardware in several different ring sizes from as small as 1/2" for a thin 1/4" stack, up to as thick as 2" for a thicker 1 ½" stack. Each mechanism features 3-rings for a traditional look, with the spacing adjusted to 2 ¾" between the rings. They feature boosters, which are the "ears" on each end that make opening and closing the rings easy and effortless, as well as a hole between the outside rings and the boosters that is the perfect fit for use with our binder rivets to attach the mechanisms to a material of your choice. You will also need a rivet setter tool to bind the rivets and your mechanism firmly to the material of choice. Many customers choose to use a 90 point or so thick custom chipboard sheet.

Every application is unique, and we would love to see your creations; you can email photos of your finished projects to info@binding101.com.

Use the chart below to determine the best half size ring binder mechanisms for you.


Ring SizeSheet Capacity*Stack Capacity*
1/2" 110 Sheets 1/4" Thick Stack
3/4" 150 Sheets 3/8" Thick Stack
1" 200 Sheets 5/8" Thick Stack
1 ½" 310 Sheets 1" Thick Stack
2" 450 Sheets 1 ½" Thick Stack

 * This is an approximation based on 20# bond copy paper. May vary depending on paper type. Stack thickness is the most accurate measure for ring capacities. Measure the stack without pressing it down.


Manufacturer US Ring
Manufacturer Part Number RINGMECHSHLF CFG
Quantity 50 Mechanisms
Color Silver
Sheet Size Half Size [5 ½" W x 8 ½" H]
Number of Rings 3-Rings
Ring Spacing 2 ¾" Between Rings [Center to Center]
Ring Shape Round Ring & Slant-D Ring Available
Sheet Capacity* [Stack Thickness] Varies Depending on Ring Size
Boosters Yes

User Reviews

You may also be interested in the following product(s)