
I have a Davidson 405-28 extension ladder that I got from Home Depot years ago (Davidson was purchased from Louisville Ladders). This is a kind of universal extension ladder. One of the end caps broke off which was annoying as the staircase wasn't stable in relation to the house at the time. I've looked around a bit and this kit from Werner seemed to meet the spec - and as you can see from the photos it did. They didn't include washers - no big deal - I just used the ones I had (small 8-32 x 5/8" screws). Make sure you know which ladder you have - because Werenr likes several different ones End Cap Kits (see attached instructions)

Black Steel Folding 2-Step Ladder With Anti-Slip Pedals, Handgrip, And 500Lbs Weight Capacity - HBTower Lightweight Portable Step Stool
22 Review

Get A Grip And Climb Higher With HBTower 2 Step Folding Steel Ladder With Anti-Slip Pedal And Convenient Handgrip - Lightweight And Sturdy With 500Lb Capacity!
28 Review

Heavy-Duty 4-Step Folding Ladder With Handgrip And Anti-Slip Pedal - Perfect For Household Use - Supports Up To 350Lbs
31 Review

Livebest Folding 2 Step Stool Light Weight Aluminum Step Ladder With A Secure Standing Platform For Office Home 330 Lbs Capacity,12" H'
13 Review

Protective And Stylish: XCEL 4Ft W X 5Ft H Black Steel Fence Gate With Anti-Rust Technology And Sharp End Pickets For Effortless Installation And Durable Outdoor Use
34 Review

Non-Slip Brown Carpet Stair Treads - 15-Pack Of 8"X30" Runners For Wooden Steps
39 Review

Ensure Safe Steps With Outdoor Non-Slip Stair Treads - 10 Pack Of 6"X40" Black Anti-Slip Strips
42 Review

IKSTAR EVA Thermal Plastic Door Cover 38" X 82": Insulated Magnetic Curtain Keeps Cool Summer, Warm Winter For AC Room, Kitchen & Stair - Brown
40 Review