RML Series A Logo    

Welded Aluminum Ladders

SERIES “A” ladders ship set-up and ready-to-use.

In addition to being lightweight, aluminum ladders are corrosion resistant and unpainted.
They are also non-magnetic.

350 lb. load rating.

  • Both the steps and the top step are 16″ or 24″ wide. The steps are 7″ deep. The top step is 14″ deep.
  • All ladders are provided with 2″ spring-loaded casters.
  • Unpainted, aluminum finish.
  • Series “A” aluminum ladders meet applicable OSHA and ANSI standards.
  • CAL-OSHA models also available.


RML Series A Logo


  • All tube members are 1” aluminum tube construction.
  • All welded construction.
  • Brightened aluminum finish.
Series A Alum Steps

8 stairway tread support welds per step, for a stronger, longer lasting, and safer ladder.

Multiple Tread OPTIONS

Cotterman® offers a variety of tread types to suit your needs. So, no matter what environment your ladder will be in, we have a tread that will offer the optimal grip.

A2 Alum step

cotterman UnaGrip Logo  (A3)

UNAGrip Ribbed Step

Ribbed (A4)

Solid aluminum step with non slip, ribbed surface.


Cotterman® offers various tread widths to accommodate almost any situation. So, it is up to you, the user, to determine how and where the ladder will be most commonly used. Our treads vary in widths from 16″ to 30″ to allow for space, storage and usage constraints or requirements.

RML Series 1000 tread 16

16″ Tread Width

Open step Premium Serrated Tread.

RML Series 1000 Tread 24

24″ Tread Width

Open step design prevents debris buildup.

On The Ground

RML Series 1000 Caster1

1-4 Step Spring-Loaded Casters

Multi-Directional Mobility. Allows 360° mobility. 1-4 step ladders have spring-loaded casters that retract whenever weight is applied.

Choose Your Series A Ladder

First Thing’s First

First, we need to determine what size ladder you need. One of the most common mistakes made in ordering many ladders is getting them too large for the available workspace. Here are some things to consider before ordering your new ladder:

Rolling Metal Ladders FTF

A: Working Height

is the approximate height that you would like to be able to comfortably reach. It is usually calculated at 5.5′ above the ladder’s platform height.

B: Overall Height

is VERY important. You want to be sure that your ladder will not be too tall to fit into your workspace. This includes being able to fit through any doors that you may need to move it through, or under any ceilings or fixtures that you may have.

C: Top Step Height

is the measurement of the top step from the ground. It’s important that this measurement is not too far above or below your desired working height.

D: Base Width

is also very important because as ladders get taller, the base width increases. It is important to be sure that the ladder will not be too wide for your workspace. We offer different tread widths to accommodate most work areas.

E: Base Length

is the measurement of how long the base of the ladder runs. This is dependent upon the height of the ladder. The taller the ladder, the longer the base. Also lower climb angles increase base length.

*Options such as deeper top steps are available, and will increase the base length. Top steps are available in 10″ – 12″(standard), 20″ – 24″, and 30″.

Product Selection Guide

Our NEW Product Selection guide can assist you in choosing the correct ladder for your application. Once you find the ladder that has the correct dimensions for you, just select the red model number, we’ll then ask you to select your tread type, tread width and platform depth. After that we’ll show you the model number(s) that is the best fit for your use.

Description Top Step Height Overall Height Working Height Short Part Number
1 Step Aluminum Rolling Metal Ladder 12 12 78 A1N
2 Step Aluminum Rolling Metal Ladder 20 20 86 A2N
2 Step Aluminum Rolling Metal Ladder 20 50 86 A2R
3 Step Aluminum Rolling Metal Ladder 30 30 96 A3N
3 Step Aluminum Rolling Metal Ladder 30 60 96 A3R
4 Step Aluminum Rolling Metal Ladder 40 40 106 A4N
4 Step Aluminum Rolling Metal Ladder 40 70 106 A4R
5 Step Aluminum Rolling Metal Ladder 50 80 116 A5R
6 Step Aluminum Rolling Metal Ladder 60 90 126 A6R
7 Step Aluminum Rolling Metal Ladder 70 100 136 A7R
8 Step Aluminum Rolling Metal Ladder 80 110 146 A8R

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