Often the products that are most intriguing result from experimental or sideline ideas. Michael Trudgen of Stealth Bike Bags sews up custom frame bags for breveteers and ramblers from his home in Eastbourne, NZ. However, recently his product list has expanded to include some innovative one-offs and limited releases. The Happy Sack is one such offshoot, and it should appeal to a broad range of users.

The Happy Sack is a simple unit, designed specifically to house one can of beer. Five years ago this would have afforded the privilege of carting round a Double Brown or similar swill – a prospect that might excite the scumbags among us, but probably not a universal boon. Nowadays, with craft brewers realising the potential for cans, it’s possible to get a fine brew in tinned form and the Happy Sack has come into its own.

The Sack’s construction is high quality, as you’d expect from a handmade unit. The stitching is straight and well trimmed, the material is very durable and there are some nice touches, such as bright coloured lining, a large Velcro area and reflective piping for a little night time safety. It’s under-engineered but in a robust and reassuring way. Stealth offers the Sack in black, grey, coloured or camo, so there should be one to suit every colourway.

For its intended use the operation is superb. First, the can slides snugly into the pouch and a top flap secures the lid via the broad Velcro closure. Then, two buckled straps loop outward from the rear centre, pass around their respective seat rails, and meet at the front of the pouch “hugging” it securely. Staying off the seatpost means the Happy Sack is dropper post compatible too. It doesn’t move much at all, and the test beer retained all of its sudsy effervescence after some reasonably vigorous descending.

If you’re not a beer drinker, or if you’re taking a break after a hard holiday season, it’ll happily house any other 330mL beverage, or a tube and some small tools. $45 online through www.stealthbikebags.com.