Shelving Options

Open Units

An Open Unit is a versatile, easy-access shelving setup with open sides and an open back—no panels or enclosure—making it ideal when you want quick visibility and fast picking. It’s a great choice for stockrooms, warehouses, and work areas where items are accessed often and airflow or visibility matters.

Common uses:

General warehouse storage
Parts and supply shelving
Backroom and maintenance storage
Areas where you want the fastest access and easiest organization

Closed Units

A Closed Unit is a shelving system designed to create a more finished, enclosed look while helping keep stored items more contained. Closed units typically use side and/or back panels (and can include a closed base option) to reduce open exposure, improve organization, and prevent items from shifting or falling out the back or sides.

Common uses:

Clean, organized storage rooms
Areas where you want a more “built-in” appearance
Spaces where small items need extra containment
Public-facing or high-traffic areas where a tidy look matters

Starter Units

A Starter Unit is the first shelving section used to begin a new row. It includes both end uprights, so it can stand on its own as a complete starting bay. Starter units are the base you build from—once the row is started, additional sections can be added to extend the run.

Common uses:

Starting a brand-new row
Single standalone shelving sections
Beginning a longer run that will be expanded later

Adder Unit

An Adder Unit is a shelving section used to extend an existing row. Instead of coming with two end uprights, an adder shares one upright with the unit next to it—so you add another “bay” without duplicating parts. This makes long shelving runs more cost-efficient and keeps the row looking clean and continuous.

Angle Posts

Angle Posts are the most common post style and are built for strength and stability. They feature a reinforced angle design that adds rigidity, making them a solid choice for general storage and applications where extra durability matters. Angle posts are also commonly used when customers want a more heavy-duty feel or added support.

Common uses:

Warehouse and stockroom shelving
Heavier storage needs
Projects where strength and stability are a priority

Delta Posts

Delta Posts are designed for a clean, finished look and easy access to your shelves. Their shape keeps the front of the unit smooth and unobstructed, which makes them a great choice for office, library, and public-facing storage. Delta posts are also useful when building continuous rows because they allow shelf placement on both sides of the post.

Common uses:

Office, library, and clean storage areas
Shelving runs with shared “common” posts
Projects where appearance and access matter most

Beaded Posts

Beaded Posts are a heavy-duty post option built for maximum strength and weight support. Their reinforced “beaded” profile adds rigidity, making them a great choice for demanding storage environments. Beaded posts also work well in continuous shelving runs where units share common posts.

Common uses:

Heavy-duty storage and higher load needs
Warehouse and industrial applications
Long shelving runs where extra strength matters

Shelf Size
(Width & Depth)

Shelf width

Width = the length of the shelf between the posts.
The catalog’s standard widths are 30", 36", 42", and 48".

How to choose width (practical rules):

Match your wall/run length: Longer runs usually use multiple bays (ex: 48" bays) to cover distance with fewer uprights.
Match your item “footprint”: If you store totes/boxes that are ~24" wide, a 48" shelf often fits two side-by-side; 36" fits one with space for labels/hand clearance.
Load matters: Capacity changes by shelf size and class; wider shelves typically carry less than shorter spans in the same class (use the capacity chart).

Shelf depth

Depth = how far the shelf extends from front to back.
Standard depths are 12", 15", 18", 24", 30", and 36".

How to choose depth (practical rules):

12"–15": small parts, smaller bins, tighter aisles, easy reach.
18"–24": the “general purpose” sweet spot for most stockrooms.
30"–36": bulky items / larger totes; best when you have aisle space and want bigger storage surface.

Reach & usability tip: deeper shelves can be harder to access from one side—so if you’re going 30–36" deep, plan the aisle and how people will pick/stock.

Shelf Capacity
Quick Guide

Choosing the right shelf size matters because capacity changes with width and depth. Below are some of the most common shelf sizes and what they typically handle.

Quick Tip: Shelf “Class” is the strength level. As you move from Class 0 → Class 2A, the shelf is built to handle more weight per shelf (when the load is spread out evenly). Use this chart to pick the class that matches what you’re storing—light supplies vs heavier bins and bulk items.

Shelf Size (W×D) Class 0 Class 1 Class 1B Class 1A Class 2B Class 2A

36×12 400 775 853 905 1205 1405

36×15 390 765 843 895 1198 1400

36×18 380 760 835 885 1182 1380

36×24 360 750 825 875 1130 1300

42×12 240 475 550 600 792 920

42×15 250 470 542 590 779 905

42×18 260 465 531 575 764 890

42×24 290 455 521 565 730 840

42×30 275 445 514 560 701 795

42×32 270 425 503 555 642 700

42×36 250 425 503 555 642 700

48×12 210 360 400 440 500 610

48×15 220 375 400 445 510 620

48×18 230 390 415 450 525 630

48×24 250 425 450 475 550 650

48×30 210 345 365 395 430 510

48×36 200 335 350 375 410 450

Need help choosing?

Tell us your shelf size (width × depth) and what you’re storing, and we’ll recommend the best option.

Call: 951-681-7259
Email: Valvargas@moonlightmfg.com

Reinforcement Options

Reinforcement is an upgrade that stiffens a shelf to handle heavier storage and reduce sagging. It mounts along the underside edges of the shelf and helps the shelf stay flatter under load.

Reinforcing Bar

What it is: A straight steel bar that bolts inside the shelf’s flange/edge.
Why choose it: A solid, cost-effective upgrade when you need more strength without changing the shelf size or class.

Best for:

Boxes, totes, and general bulk storage
Customers who want added strength but don’t need the most rigid option

Reinforcing Angle

What it is: An L-shaped steel angle that bolts inside the shelf’s flange/edge.
Why choose it: Typically provides a stronger “anti-bend” structure than a flat bar because the L-shape resists flexing better.

Best for:

Heavier loads
Shelves that tend to sag in the middle
Tougher warehouse/industrial use

Front Only Reinforcement

What it does: Reinforces the front edge of the shelf (the edge you see and load from most often).
Why choose it:

Helps prevent the “front lip” from flexing
Great for most everyday storage where loads are fairly balanced

Best for:

Standard shelving use
Items loaded from the aisle side
When budget matters but you still want a noticeable strength upgrade

Front + Rear Reinforcement

What it does: Reinforces both the front and rear edges of the shelf.
Why choose it:

Adds the most stiffness and stability
Helps reduce overall sag and twisting
Better for heavier storage or deeper shelves where the back edge also carries load

Best for:

Heavier or denser storage
Deeper shelves (like 24"+) where weight spreads farther back
When you want the strongest, most stable feel