Binder Spine Mechanisms

Ring binder mechanisms are the ring devices found on the spines of standard binders. We offer a large selection of binder mechanisms for binders with two, three, or six rings. Our selection includes a wide array of binder rivets in multiple sizes and colors to suit any application. Ring binder spines can be used to creatively bind your documents, or create your own custom binders and agenda books. You can even pair binder ring hardware with our rivets and rivet setter tool to make your own customized binders.

This binder hardware is often used by production and manufacturing plants that choose to produce their own custom binders in-house. They are also particularly useful for real estate agencies, legal offices, or arts and crafts businesses.

Choose from a variety of letter-size, half size, and memo size ring binder mechanism spines for your binding needs. Quantities start at 50 pieces per box and the quality is unmatched.

Bulk discounts are available; call (866)537-2244 to see if your order qualifies


3-Ring Letter Size Silver Binder Mechanisms (Price per Box)3-Ring Letter Size Silver Binder Mechanisms (Price per Box)

3-Ring Letter Size, Silver
Boxes of 50 Spines

Letter size silver ring binder spines are the most popular choice, offering the largest variety of ring sizes and shapes in-stock. Ring sizes available include 1/2" to 3" in a round-ring style, or 1" to 4" in an angle-D ring style. Our letter size, silver ring mechanisms are packaged with 50 spines per box. They have 3-rings with a standard hole spacing of 4-1/4" between the rings, making them compatible with any standard letter hole puncher

3-Ring Letter Size Black Binder Mechanisms3-Ring Letter Size Black Binder Mechanisms

3-Ring Letter Size, Black
Boxes Starting at 144 Spines

These ring binder spine mechanisms are made for letter-size 11" binding edges and are finished with a gorgeous matted black coating. They are available in a round ring style with 1/2", 3/4", 1", and 1.5" ring diameters. The packaged quantities vary by ring size, boxed with between 144 to 200 spines. This bulk quantity makes them ideal for larger groups looking to manufacture many binders. They feature boosters on each end of the spine so you can easily open your rings without risking damage to the closure.

3-Ring Letter Size Brass Binder Mechanisms3-Ring Letter Size Brass Binder Mechanisms

3-Ring Letter Size, Brass/Gold
Boxes Starting at 54 Spines

These vibrant brass/gold binder spines are made for standard North American letter-size 11" binding edges. They are available in a round ring style with 3/4", 1", 1.5", and 2" ring diameters. The packaged quantities vary by ring size, boxed with between 54 to 200 spines. They feature booster tabs on each end of the spine so you can easily open your rings without risking damage to the closure.

Half Size 3-Ring Binder MechanismsHalf Size 3-Ring Binder Mechanisms

3-Ring Half Size, Silver
Boxes of 50 Spines

Half-size binder mechanisms work perfectly with half sheet papers. Our mini 3-ring half-size binder mechanisms work perfectly with half sheet papers measuring 8-1/2" high and 5-1/2" wide. The ring spacing is 2-3/4" between each, and there are boosters on each end for easy ring opening. Each binder spine is made of durable metal. Rings are round and sizes available include 1/2", 3/4", 1", 1-1/2", and 2" diameters. Mini binder parts are silver in color, and sold in boxes of 50.

2-Ring Binder Mechanisms (Box of 50)2-Ring Binder Mechanisms (Box of 50)

Two-ring binder spines are used most commonly for top-binding letter size 8.5" x 11" paper, as well as for custom and unique binders, scrapbooks, and swatch books. These metal spines do not have any boosters, so sheet size is not limited. You can buy top bind letter-size 2-ring binder mechanisms online in either 1" or 1-1/2" ring sizes, and in round or straight-d ring shapes. The two rings on this ring binder hardware have standard 3-1/8" spacing between the rings and are packaged with 50 pieces per box.

Memo Size 6-Ring Binder Mechanisms Memo Size 6-Ring Binder Mechanisms

6-Ring Memo Size, Silver
Box of 300 Spines

Memo size binder spines are a great choice for clients that need to make their own memo-sized ring binders. The six rings are separated into two groups of three, with 3/4" between each ring, and 1-1/2" between the two groups. The rings come in a traditional round shape, and boosters on each end of the binder mechanisms make opening the rings hassle-free. The standard insert size for memo size measures 6" high for the binding edge, and 4" wide. Memo size ring binder spines are made of durable metal in attractive silver color. They are sold in a bulk box of 300 spines.

Binder Rivets (Pack of 100)Binder Rivets (Pack of 100)

Combine these rivets with ring binder mechanisms, a rivet setting tool, and your own covers of choice to create your own binders. Push your rivet of choice through your cover and then through the mechanism, making sure that the flat face is on the outside of your cover. Then use the setter tool and a hammer to wrap the rivet, binding it to the top of your mechanism. Be sure to use an extremely strong and hard surface as your base, otherwise, the rivet may not set properly. Buy binder rivets online in several sizes, depending on your cover thickness, as well as in either white, black, or silver, all packaged with 100 pieces per bag.

Rivet Setter ToolRivet Setter Tool

Rivet Setter Tool
Sold Individually

When you buy this rivet setting tool online, you can pair it with our binder mechanisms and rivets to can make your own binders, unique mounted swatch displays and more. To use, just place a rivet through your own pre-punched cover of choice and the mechanism and, using a very hard and strong work base, hit the inside of the rivet firmly with a hammer. The unique rivet setter tool shape turns the rivet opening on itself, creating a bind to your mechanism.


Ring Capacities

Sometimes customers will choose a ring spine based on the size indicated, not understanding that the ring size is not the same thing as capacity; it is actually the inside diameter of the ring itself, and the capacity is less. In this ring binder mechanism capacity chart we lay out the various ring diameters and both their stack capacities and sheet capacities.

Ring Diameter Stack Capacity Sheet Capacity*
1/2" 1/4" 110 Sheets*
3/4" 3/8" 150 Sheets*
1" 5/8" 200 Sheets*
1-1/2" 1" 310 Sheets*
2" 1-1/2" 450 Sheets*
2-1/2" 2" 540 Sheets*
3" 2-1/2" 650 Sheets*
4" 3-1/2" 850 Sheets*

*Sheet capacity was calculated using standard 20 lb. bond copy paper and will vary depending on the paper stock you are binding, any index tabs or page protectors included, etc. For this reason, the most accurate capacity measurement will be the stack capacity, which is calculated by laying the stack loose and measuring the thickness while not pressing down. This allows for easy page-turning.


Ring Binder Mechanism Comparison Chart

 Letter SizeHalf SizeMemo Size
Color Silver Black Brass/Gold Silver Silver Silver
Rings 3-Rings 3-Rings 3-Rings 2-Rings 3-Rings 6-Rings
Page Size 8.5" W x 11" H 8.5" W x 11" H 8.5" W x 11" H 8.5" W x 11" H (Short-End) 5.5" W x 8.5" H 4" W x 6" H
Ring Size 1/2", 3/4", 1", 1.5", 2", 2.5", 3", 4" 1/2", 3/4", 1", 1.5" 3/4", 1", 1.5", 2" 1", 1.5" 1/2", 3/4", 1", 1.5", 2" 3/4"
Ring Shape Round & Slant-D Round Round Round & Straight-D Round Round
Base Length 11-1/4"-11-3/8" 11-1/4"-11-3/8" 11-1/4"-11-3/8" 5"-5-1/4" 8-7/8"-8-15/16" 6-3/16"
Base Width 13/16"-1-3/4" 13/16"-1-3/4" 13/16"-1-3/4" 13/16"-1" 12/16"-1-7/16" 13/16"
Ring Spacing 4-1/2" 4-1/2" 4-1/2" 3-1/8" 2-3/4" 2 Groups of 3
3/4" Between Rings
1-1/2" Between Groups

More Info About Letter Size Binder Mechanisms

Letter size, sometimes called US letter, is the most popular paper size in North America, including the United States, Canada, and parts of Mexico. When you pick up a ream of paper from the store, you will almost always be looking for a letter-size sheet. These pages measure 8.5 inches wide and 11 inches high (or 216 millimeters wide and  279 millimeters high). Sometimes they are called size "A", however, this is not to be confused with A4 which is the closest ISO (international system of paper sizes), but is slightly taller and narrower.

These ring binder spine mechanisms are made for letter-size 11" binding edges. They have three rings with a standard hole spacing of 4.25 inches between the rings. They are available in silver, matte black, or a gold/brass finish. All options feature boosters on the ends that allow for easy opening of the rings without risking damaging the rings themselves or the closure integrity. They have two rivet holes, one on each end, that are spaced 3/4 inch from the short end, and 9-1/2 inches from each other. The length of the base itself ranges from 11-1/4" to 11-3/8", varying only slightly based on the ring size.

More Info About Half-Size Binder Mechanisms

Half-size ring binder mechanisms are built for, you guessed it, half-size paper! These sheets are half of a letter page, measuring 5.5 inches wide and 8.5 inches high (basically if you fold a letter-size sheet "hamburger style"). Take a letter-size sheet, fold it in half, turn it 90 degrees, and that is the sheet size compatible with these binder spine pieces.

Mini binder rings are spaced 2-3/4 inches apart, and each mechanism features boosters for easy opening. Round ring sizes are available from 1/2” to 2”, with some select sizes also available in slant-d style. Whether you are manufacturing binders, making swatches, church directories, or anything else, half-size binding mechanisms may be a great fit.

More Info About Memo Size Binder Mechanisms

Memo size mini binder mechanisms have 6-rings and easy-open boosters on each end. These 6-ring binder spines are most often used in planners, calendars, and mini journals. They are intended for use with standard memo size paper, which is 6 inches high and 4 inches wide. Boosters on each end make it easy to open the rings.

Ring sizes are available in either 1/2” or 3/4”. The rings are grouped in two sets of 3. Each ring is 3/4 of an inch apart, and there is 1-1/2” between the groups.

More Info About 2-Ring Binder Mechanisms

2-Ring binder mechanisms are the simple metal spine piece found in two-ring binders. These binder spines are most commonly used on the top, the short end of a letter-size paper that measured 8-1/2" wide. The top binding method is almost always used in medical offices and other corporations where pages need to be filed into a cabinet when not being used for reference.

The rings are spaced 3-1/8" apart and fit into standard 2-hole punched pages. The binder mechanism base measures 5-1/8” long and 1” wide, and there is a hole on each end to allow for rivets. 2-ring binder spines are available in round and straight-d ring shapes, as well as 1” or 1-1/2” ring sizes. This measurement is the inside ring diameter at the widest point.

Plastic Letter Size Binder Mechanisms

Plastic ring binder mechanisms combine the functionality of a ring binding spine with more options for colors, as well as a more unique look.

Made of ABS resin, these plastic binder ring parts are available in black, navy blue, gray, or an off-white beige. Their peg-and-hole closure is unique for binders and ensures the rings stay shut until you open them with the boosters on the end.

The rings on these binder spines are 1" in diameter, which is rated to hold approximately 225 sheets of standard 20 lb. copy paper, or about a 5/8" thick stack of materials. They feature three rings that are spaced 4 ¼" apart from each other, which is the standard US spacing for letter size 8 ½" wide by 11" high paper. That means you can use them with any of our standard 3-hole punches, and pair them with full size index tabs.

Although primarily made of this plastic, the back does have a metal plate for added strength. Pair these ring binder spines with rivets to make your own binders or planners. They are sized for standard letter-size documents and pape


Ring Mechanism Inspiration