The Hollis SMS Katana 2 is a premium sidemount system developed in collaboration with Edd Sorenson of Cave Adventurers. Bringing practical sidemount experience into its design, it combines comfort, easy adjustment and a streamlined profile for recreational and technical diving.

Its Quick Fit System lets you tailor the harness to your body, while the low-profile wing provides 18 kg of lift without unnecessary bulk. From your first sidemount course to more advanced configurations, the Katana 2 offers flexibility as your skills and equipment needs develop.

Our current stock is the single-bladder version. For a dual-bladder system, please contact the Aquamaster team to discuss availability and arrange your order.

Hollis SMS Katana 2 Features and Benefits

• Quick Fit System adjusts torso height to accommodate smaller and larger divers
• Low-profile wing helps reduce bulk and drag in the water
• 18 kg lift capacity supports appropriate sidemount configurations
• 9 kg integrated weight capacity provides ballast storage for different exposure suits and diving conditions
• H or Y harness configuration lets you choose your preferred arrangement
• Easy-reach attachment points keep accessories accessible along the sides of the wing
• Top dump valve allows gas venting without reaching behind the wing, helping maintain trim
• Integrated sidemount CCR mount supports compatible rebreather configurations
• Single-bladder configuration currently in stock

Continue reading below to explore the key features and technical specifications.

Hollis SMS Katana 2 Quick Fit Adjustment for a Personalised Setup

The QFS Quick Fit System allows fine adjustment of the harness torso height, helping divers of different sizes achieve a comfortable, secure fit.

You can configure the harness in an H or Y arrangement, depending on your preference. This allows you to refine the fit and equipment positioning with your sidemount instructor, whether you are learning the basics or adapting an established setup.

Low-Profile Wing for Streamlined Diving

The Katana 2’s wing delivers lift while keeping your profile compact. Its design helps avoid the bulky “turtle shell” shape that can increase drag.

An accessible top dump valve lets you release gas without reaching behind the wing, helping you maintain your position and trim. Attachment points along the sides keep accessories within reach.

Adaptable for Warm and Cold Water

Designed for use with steel or aluminium sidemount cylinders, the Katana 2 accommodates a range of equipment arrangements.

Its integrated weight system holds approximately 9 kg of ballast, providing options when using drysuits or thicker exposure protection. The weight pockets are non-ditchable, with ballast positioned behind the Quick Fit System.

Your cylinder choice, exposure protection and individual buoyancy requirements determine the appropriate weighting and configuration.

Single- or Dual-Bladder Configuration?

The single-bladder version currently stocked by Aquamaster suits recreational two-cylinder sidemount diving. It can also form part of an appropriate drysuit configuration where the drysuit provides an alternative source of buoyancy.

The dual-bladder version offers separate buoyancy redundancy for applications such as technical diving in a wetsuit.

Choose the configuration appropriate to your training and dive requirements. If you need a dual-bladder system, please contact the Aquamaster team to discuss availability and arrange your order.

Technical Specifications

Hollis SMS Katana 2 System Specifications

Who It’s For

The Hollis SMS Katana 2 suits divers beginning their sidemount training as well as experienced sidemount divers seeking an adaptable system.

Its adjustable harness helps new sidemount divers establish a comfortable fit, while flexible configuration options accommodate more advanced setups. It is also useful for divers moving between warm- and cold-water environments, different cylinder materials, or wetsuit and drysuit use.

Support from Aquamaster Thailand

Contact Aquamaster Thailand for fitting advice, configuration options and after-sales support. Our team can help you assess whether the single-bladder Katana 2 suits your equipment or assist with ordering the dual-bladder version.