Overeem Port Cask Distiller's Strength is a Tasmanian single malt from Old Hobart Distillery in Hobart, matured for a minimum of five years in 100-litre ex-port casks — broken down and rebuilt from large 600-litre port pipes by a local Tasmanian cooperage to accelerate interaction between spirit and wood. Port cask maturation contributes rich red and dark fruit character: plum, dried cherry, dark berry, and underlying vanilla from the oak. Overeem's use of port casks is a defining feature of the distillery's range — the style is well suited to the fruit-forward character of the Tasmanian new-make spirit. Bottled at 43% ABV without chill-filtration, preserving the texture and intensity of the aged spirit.

Overeem Whisky is produced in Hobart, Tasmania — founded by Casey Overeem in 2005 as Old Hobart Distillery, with the first casks filled in 2007. Overeem was the fourth whisky distillery established in Tasmania and is considered one of the founding distilleries of Australian whisky. The distillery produces small-batch single malt whisky of around 8,000 bottles annually, drawing on Tasmanian barley and water and maturing spirit in a selection of port, sherry, bourbon, and PX casks. Casey Overeem sold the distillery in 2014; his daughter Jane subsequently bought back the Overeem brand and whisky stocks in 2020, re-establishing family ownership of the marque.