This website is under construction. Please revisit in two weeks. Dismiss

SKB 1SKB-R904U20

SKB 4U Roto Shockmount Rack Case
20″ (51cm) Deep Rail to Rail

Based on the Ultimate Strength Series design, the Roto Shockmount Rack Cases provide added protection for sensitive gear. With an internal frame mounted on adjustable elastomer shock absorbers on all eight corners, this …

Interior Width:  19.00 in  (48.26 cm)
Interior Height:  7.00 in  (17.78 cm)
Rackable Depth:  20.00 in  (50.80 cm)
Rack Units Total:  4 Unit

Need assistance finding the right rack? Call or contact us to speak to SKB Rack Specialist.

£520.63 (exc VAT)
£624.76 (inc VAT)

We can often improve on our online prices if you contact us direct.

See our BEST PRICE page.



SKB 4U Roto Shockmount Rack Case

Based on the Ultimate Strength Series design, the Roto Shockmount Rack Cases provide added protection for sensitive gear. With an internal frame mounted on adjustable elastomer shock absorbers on all eight corners, this revolutionary design controls the effects of shock and vibration on all three axes. The “sway” space around the internal frame provides natural air conditioning — very important for delicate equipment.

The SKB 1SKB-R904U20 also save big on weight versus traditional flight cases and wooden cases. These models well accommodate audio mixers, video recording devices and communication equipment such as routers, switches etc. Typical applications are in broadcast, music, pro audio, outdoor events and many more markets.

SKB Rack Cases Part 1
Introducing SKB Racks

SKB Rack Cases Part 2
How to select the right rack case

SKB Rack Cases Part 3
Into more detail

SKB Rack Cases Part 4
Testing Fun – Do Not Try At Home!

Rackable Depth


Rail Type

Unit Size


Features & Specs


SKB 4U Roto Shockmount Rack Case

  • Threaded steel rails
  • Rear rails
  • Shock resistant
  • Optional caster kit
  • Roto molded for strength
  • Adjustable elastomer shock absorbers
  • Molded-in handles provide secure grasping points
  • Interlocking X-pattern for solid stackability
  • Front and rear full size lids
  • Recessed latches
  • Shock absorbing feet
Interior Width
19.00 in
48.26 cm
Interior Height
7.00 in
17.78 cm
Exterior Depth
27.00 in
68.58 cm
Exterior Width
27.65 in
70.23 cm
Exterior Height
15.63 in
39.70 cm
Rack Space Units Total
Rack Depth Rail to Rail
20.00 in
50.80 cm
Rack Depth Front Rail to Back Lid
23.00 in
58.42 cm
Lid Depth
2.25 in
5.72 cm
Shipping Weight
40.00 lb
18.14 kg
Product Weight
36.00 lb
16.33 kg
1.25″ sway space front and rear of the case.

Options & Accessories


SKB 4U Roto Shockmount Rack Case

1SKB-1916 – Shockmount Roto Caster Kit

1SKB19-AC1 – Rack Mount Hardware

3SKB-BB60 – Small Accessory Pocket

3SKB-BB61 – Large Accessory Pocket

3SKB-BB62 – Caster Accessory Bag

3SKB-SA – Shock Absorber Kit

3SKB-SR20 – 20” Support Rails



SKB 4U Roto Shockmount Rack Case

SKB Roto Shock Racks Brochure

SKB Warranty

SKB Cases Lifetime Warranty

SKB Lifetime Warranty
SKB brand hardshell rack cases are fully warranted against defects in materials and craftsmanship for the life of the case to the original owner. That means, if your case breaks, SKB will supply replacement parts, repair the case, or replace your case for as long as you own it. Proof of Purchase is required for all warranty claims.
SKB Soft cases and gig bags are only warranted for one year from date of purchase.
SKB Rack Cases (this website) will arrange free of charge collection of warranty goods and SKB Cases Inc will cover all of the costs of repairs and/or replacements, as well as the return shipping. Please see our Warranty Page for full details of how we can arrange a free collection.
SKB hardshell rack cases are warranted for life to the original owner only. Cases used for rental purposes, used by institutions or schools, modified or used cases are not covered by this warranty.


Frequently Asked Questions

Whom do I call for SKB replacement parts?
Please call or email us with your requirements. Full contact details can be found on our Contact Page
What do I have to do before I return my SKB case or SKB rack for repair?
Please see our Returns Page for full details and we will arrange free collection..
Does a SKB Warranty Card come with my case?
No warranty card is necessary. Just remember to keep your proof of purchase.
Where will I find my model number on my SKB case?
It is not on your case. You will find the model number on your original proof of purchase receipt. That is why it important to keep your original receipt.
How long will a repair take?
Usually SKB about two weeks from the time we receive your case.

Flight Cases

3D Flight Cases as owners of this site are UK manufactures of custom built flight cases and 19” Racks. If you cannot find what you are looking for in the SKB product range, we can probably help. Our 19” Racks can be built to any unit height and any depth, with or without an inner welded steel shock mounted frame.
Our Shock Mounted Server Racks can carry as standard up to 600kg. 3D flight cases are of professional touring quality and are designed for the most demanding and daily use.
For examples of our cases please visit our Flight Case Gallery.
SKB vs 3D Flight Case
Disadvantages: Heavier than an SKB Rack and not watertight.
Advantages: 3D Racks are bespoke built to any size and shower proof.
3D Cases 28U Portable Server RackInner Shock Mounted FrameRugged Transportable Server Rack33U Shock Mounted Server RackShock Mounted Rack With Inner Security Doors

Your Basket: