Chris Butler designed and built a seminal range of small but tough offshore cruisers that found themselves in all corners of the world. They sold in large numbers for the times (late 60s to late 70s). Performance across the range tended to be moderate to good and the interiors on the small side due to narrow beam, but their strong suit was sea-keeping and the ability to keep going in difficult conditions. Butler competed in AZAB and OSTAR races in the Achilles 24, which featured a bulbed fin keel. This gave the boat quite respectable speed and windward performance but a triple-keeled, shoal draught version was much more pedestrian. She has four berths, a small galley and a rudimentary toilet. Headroom was just 4ft 8in (1.37m). Most of the 350-plus built were originally sold without engines and many will still use outboards, but an inboard petrol engine was an option, usually quickly replaced with a small diesel. Factory-built boats were sound, strong but simple. The quality of the many home-built models will be variable.

LOA 23ft 9in (7.24m), LWL 19ft 6in (5.94m), beam 7ft 1in (2.16m), draught 3ft 9in (1.14m) or 3ft (0.91m), displacement 2.600 lb (1, 180kg). Price guide: £2,000 to £5,000.