5 Aluminium Scuba Cylinders to Compare for Fit and Length
A shorter cylinder can change valve reach and how a setup sits, but it also changes available gas and buoyancy. This guide compares five mid-to-large S-series bodies. It is a physical-fit comparison to use after capacity needs are established, not an instruction to downsize a cylinder for convenience.
Updated · Manufacturer specifications and published review evidence
How we chose and ordered these picks
S80 provides the reference point, followed by progressively shorter alternatives in our current coverage. Confirm mounting and buoyancy for each exact model.
List position is an editorial recommendation, not a review score. The selection uses the documented features and limitations below. We have not personally tested this equipment. Verified publisher scores, where available, are shown separately and link to their evidence. Our catalogue is still being researched; inclusion does not mean a product has a completed scored review.
The shortlist at a glance
Choose a model to jump to its details. Compare the exact configuration before ordering.
Catalina’s S80 is an aluminium scuba cylinder with 11.1 litres of internal water capacity and a 207 bar working pressure. Despite the familiar “80” name, Catalina lists 77.4 cubic feet of air capacity. Its broad 184.2 mm diameter and 14.2 kg cylinder weight matter when checking harness fit, transport and handling.
Material
6061 aluminium
Water capacity
11.1 L
Air capacity
77.4 cu ft / 2192 L
Service pressure
3000 psi / 207 bar
Dimensions
184.2 mm diameter × 658 mm cylinder length
Cylinder weight
14.2 kg
Listed buoyancy
-1.6 lb full; +2.8 lb at 500 psi; +4.1 lb empty
What to check
The manufacturer lists buoyancy changing from -1.6 lb full to +2.8 lb at 500 psi. Account for that change in the complete rig rather than treating it as a fixed ballast contribution. Confirm the actual valve, cylinder markings and local filling acceptance before purchase. Social Diving’s pressure and height figures differ from Catalina’s cylinder table; the manufacturer values are used here.
Published review score: 96/100★★★★★★★★★★4.80/51 rated publisher group(s) · not the position in this list
S63 is Catalina’s shorter alternative to the familiar S80 format. The official specification sheet gives 9.0 litres of water capacity and 63 cu ft air capacity in a 551 mm cylinder. Its 184.2 mm diameter matches S80, but its listed weight is lower at 12.2 kg.
Water / air capacity
9.0 L / 63 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
184.2 × 551 mm
Cylinder weight
12.2 kg
Buoyancy: full / 500 psi / empty
-2.8 / 0.7 / 1.8 lb
What to check
The product page ambiguously lists water capacity as “11.1, 9”; the manufacturer’s specification sheet identifies S63 as 9.0 litres. Its buoyancy reaches +1.8 lb empty. Check the valve and total rig rather than treating a shorter cylinder as a direct substitute for the larger supply.
No verified independent overall score yet. Compare the specifications and limitations above.
S53 is a 7.6-litre aluminium cylinder with 53 cu ft of air capacity. Its 184.2 mm diameter matches S63 and S80, but the body is only 488 mm long. Catalina lists 11.4 kg, making this a short cylinder rather than an especially light one.
Water / air capacity
7.6 L / 53 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
184.2 × 488 mm
Cylinder weight
11.4 kg
Buoyancy: full / 500 psi / empty
-3.8 / -0.8 / 0.1 lb
What to check
The listed buoyancy is -3.8 lb full, -0.8 lb at 500 psi and +0.1 lb empty. Compare those figures with the regulator-equipped rig you will use. Older third-party charts list different weights and buoyancies; they should not override the current manufacturer table.
No verified independent overall score yet. Compare the specifications and limitations above.
Exact-model photo not yet verified. See the manufacturer specifications for dimensions.
S50 provides 50 cu ft of air in a 7.2-litre aluminium cylinder. Its 175 mm diameter matches S45, while the 493 mm body adds capacity with a listed weight of 9.9 kg. It is narrower than the S53 despite their similar overall size.
Water / air capacity
7.2 L / 50 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
175 × 493 mm
Cylinder weight
9.9 kg
Buoyancy: full / 500 psi / empty
-2.4 / 0.4 / 1.2 lb
What to check
The specified buoyancy becomes positive near the end of the fill: +0.4 lb at 500 psi and +1.2 lb empty. Valve and rigging choices alter the assembly. The manufacturer page has no verified exact-model photo, so a logo is no longer shown as the product.
No verified independent overall score yet. Compare the specifications and limitations above.
Exact-model photo not yet verified. See the manufacturer specifications for dimensions.
S45 is a short, relatively broad aluminium cylinder with 6.4 litres of water capacity and 45 cu ft of air capacity. Its 450 mm length is useful to compare against taller cylinders, while the 175 mm diameter and 9.2 kg weight prevent it being mistaken for a narrow stage bottle.
Water / air capacity
6.4 L / 45 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
175 × 450 mm
Cylinder weight
9.2 kg
Buoyancy: full / 500 psi / empty
-2.8 / -0.3 / 0.5 lb
What to check
Catalina lists buoyancy moving from -2.8 lb full to +0.5 lb empty. The official page currently supplies a placeholder rather than an exact product photo; the previously assigned logo has been removed. Check local supply and valve options directly.
No verified independent overall score yet. Compare the specifications and limitations above.
Product research checked 2026-10-03. Specifications can change; confirm the exact model and package.
Before you buy
Compare actual cylinder length and diameter with the harness.
Account for buoyancy near the end of the dive, not just full-cylinder weight.
Check that a shorter body still gives suitable valve access and band placement.
Take two or three suitable models from this list into a comparison, then remove any that fail your fit or compatibility checks. A lower position here can still be the better purchase for your setup. Check the product page for source dates and unresolved details before placing an order.
Can I choose a cylinder by my height alone?
No. Body fit matters, but capacity, buoyancy, configuration and the planned gas requirements must also be satisfied.
