Buying a used rotary topper can be a game of spot the difference with McConnel also building Twose-badged machines from its plant in Ludlow, Shropshire. Fellow Alamo Group members, Bomford and Spearhead, produce toppers in Salford Priors, Worcestershire. There is model cross fertilisation, but there are specification differences between various models and certain components.

McConnel launched the SR15-6 flex-wing topper in 1994, its 4.6m width matching a growing demand for not just a pasture topper but a machine that could mulch longer crop stubbles, too. Evolved into what is now the SR15 Classic, it was joined by a different design, the SR series, from 2005. These span working widths from 4.20m in mounted form and 4.60m, 6.20m and 8.20m trailed