Features of All Worthington X-Series Cylinders

• Hot-dip galvanized external finish
• Five-year limited warranty
• Both U.S. DOT-E14157 and Canadian TC-SU4957 markings
• 0.750-14 NPS (3/4 NPS) threaded neck opening
• Manufactured in North America

These cylinders are made at Worthington's state of the art manufacturing
facility in Tilbury, Canada. Worthington manufactures these cylinders using
deep-drawn chrome molybdenum steel resulting in a light weight cylinder
with excellent buoyancy characteristics.

How to Select a SCUBA Tank

Our factual but easy-to-read article helps you make
this big decision by giving you information on:

• Aluminum tanks versus steel tanks
• Low-pressure tanks versus high-pressure tanks
• Tank paints, coatings, and finishes
• Tank dimensions and capacity recommendations

to read How to Select a SCUBA Tank.

The Dive Gear Express "Deluxe Complete" Setup Includes:

• Cylinder w/Anti-Roll Boot
• Pro DIN/K Valve
• Spare Viton O-ring for Valve Face
• Valve Protector Cap
• Full Visual Inspection

Dive Gear Express offers diving products labeled Nitrox Ready, whose oxygen-compatible components are free of hydrocarbons and other contaminants. With Dive Gear Express, you don't have to make expensive aftermarket alterations to use oxygen-rich gas mixtures.

to read What Does Nitrox-Ready Mean?

Dive Gear Express ships your cylinder with the valve installed. Unless you order another valve or manifold, the valve is the Thermo Pro DIN/K valve suitable for use with both DIN or Yoke regulator fittings. Your cylinder ships with a few PSI pressure of oxygen compatible air necessary to keep the interior dry. The cylinders have a current month Visual Inspection Sticker; no re-inspection is necessary before filling. SCUBA Tanks must be hydrostatically tested every five years (60 months). The primary steel cylinders typically have a factory hydro date between 3 and 9 months old, but not more than 12 months old.

How Steel Cylinders Are Made

Click on the play arrow to view the video. A high speed internet connection recommended for best viewing.

Video is © Worthington Cylinders

Variable Capacity of Cylinders

One idea we like is selecting a larger capacity cylinder and then deliberately under fill. For example the X7-100 yields 89 cubic feet at 3000 psi, and the X8-119 yields 107 cubic feet at 3000 psi. That is plenty of gas for most dives, puts an end to short fills, and the lower pressure is easy on equipment, yet allows the option of a high-pressure fill when you need really need more gas. This is how divers have for years been using overfilling with low-pressure cylinders, but with the advent of the large-capacity high-pressure cylinders, it eliminates the concerns regarding overfills.

What Happened to Low-Pressure Cylinders?

Many experienced divers have preferred low-pressure cylinders because they are easier on regulators, have no short-fill concerns, and are more suitable for partial-pressure blending. More recently, the low-pressure 3AA cylinders (2640 psi, i.e., 2400 with a +) are being replaced by the new DOT exemption cylinders (3442 psi, no plus needed). That's because you can use the high-pressure 3442 psi cylinders as low-pressure 2650 psi cylinders if you prefer, simply by under filling. The 3442 psi DOT Exemption cylinders have the same length, diameter, and capacity at lower 2640 psi pressure as the 3AA cylinders. Even better, the empty weight of the new cylinder design has been reduced slightly, yet the buoyancy remains slightly negative when empty.