Swiftech recently launched it’s lineup of quick disconnect fittings (QDCs) under it’s “Lok-Seal” product line. These use the standard twist method to separate but bring some interesting new features:
This is the standard QDC pair. You can not buy these individually or with different outputs however you can buy different outputs or supply your own. The pair comes in a box:
Splitting the pairs apart we see the QDC end with the central section that seals the flow and a locating pin/divot for centering the fittings:
The pair comes with one female G 1/4 thread at either end and is the only version of the QDC pair you can buy. However you can change this by buying accessories. The accessories come in little blister packs:
Swiftech sent a variety of the interchangeable accessories:
Top Row: 1/2″ ID x 3/4″ OD Compression Fitting, 3/8″ ID x 5/8″ OD Compression Fitting, Male G 1/4 Threaded Fitting Bottom Row: 1/2″ ID x 3/4″ OD Compression Fitting, 3/8″ ID x 1/2″ OD Compression Fitting, Panel Fitting with Female G 1/4 Threaded Fitting In order to fit these you can use two wrenchs, one on the cap to the QDC fitting, and one on the body. Thankfully Swiftech provided wrench flats on these. They tried to make it subtle though and so it’s not the normal hex pattern. A few turns on the cap and it’s off:
This is the male QDC, and the next photo is the female QDC where the cap also constrains the spring that provides the sealing:
The spring makes it a little harder to replace the cap, but it’s really not hard. Of course you don’t have to buy the accessories, you can use accessories you already own. For example if you have an unusual tubing size that isn’t supported, you could simply choose to attach your fittings to the QDC. In this shot the top is a QDC with rebranded Swiftech compression fittings added to the standard QDC base. At the bottom we see the QDC with the same size compression fittings fitted:
As can be seen, there is a space saving when using the accessories rather than providing your own fittings. This means that the Swiftech QDC system is the shortest that I have (Swiftech is the bottom pair):
Even when fitted with the male G 1/4 fitting it still gives a very small foot print ( (Swiftech is the bottom pair):
This makes it ideal for small spaces, for example when attaching directly to a radiator or a GPU. CPUs are normally constrained by the fatness of the fitting rather than the length. It’s also perfect for running in line with some tubing. However we can see that the QDC is no larger than the swiftech 1/2″ ID x 3/4″ OD diameter fitting, so if you can fit that fitting on your block then you’ll be fine. I tested the following cpu blocks to see if they could fit the Swiftech 1/2″x3/4″ compression fitting:
Performance The Lok-Seal fittings perform similarly to Koolance’s mainstream QD3 and VL3N fittings:
Price The Lok-Seal fittings are by far the most expensive option. I consider two main use cases. The first is in line with some tube and for this I would have 1/2×3/4 compression fittings on either end. The second is fitting to a block or a radiator. This involves a male G 1/4 on one side and a compression fitting on the other:
As can be seen the Swiftech is ~50% more expensive than the Koolance fittings. Having said that the price may not be a concern to those with high end systems who simply can not fit the longer Koolance fittings.
Summary The Swiftech fittings bring a nice idea to the table with interchangeable heads and a compact footprint. I applaud them for trying to innovate rather than just copy the status quo. However the higher cost means that unless you are space constrained it’s hard to justify over the similarly performing Koolance QD3. The QD4 is even better in terms of flow, but is a bit of a monstrosity. The ideal QDC would have the push to release mechanism of the Koolance QD series, the flow of the QD4, the price of the QD series and the footprint and interchangeability of the Swiftech. However price is not something that should stop this product being recommended. It’s not perfect but it is a solidly performing option to consider as space is often what stops people from using QDCs.
8/10 – One point docked for price, and one point for the twist mechanism not being as nice as the Koolance one
