Monster has confirmed the expansion of its iSport headphone range with the addition of its first-ever wireless in-ear models – including what it describes as the "world's slimmest" sports buds.

The latest products to join the iSport family, some of which were first on show at CES, are the iSport SuperSlim (£130, above) and iSport Wireless (£80, below). Not only that, but its wireless iSport Freedom on-ears are now available in a new finish.

According to Monster, the new in-ear headphones are designed to be "in tune with users' active lifestyles" thanks to features including water resistance, patented ear hooks and angled ear tips.

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The manufacturer says its iSport Wireless SuperSlims can be worn under your cycle helmet due to its "feather-light" construction. The Wireless SuperSlims also boast a wireless range of 50ft.

In comparison, the iSport Wireless buds have a range of 30ft – but both models claim to offer the same five hours of playback between charges to keep the tracks going – even if you've stopped.

Like all other iSport headphones from Monster, the new in-ears come with washable and sweat-proof materials; audio technologies such as Pure Monster Sound; and a secure fit.

MORE: Monster iSport Freedom "washable" headphones get aptX Bluetooth

More after the break

Meanwhile, the iSport Freedom on-ears (£230) are now available in a Business Black finish and join the rather striking neon green version that made their first appearance back in 2013.

Head Monster, Noel Lee, said: "Headphones have become an essential piece of workout gear for athletes and serious workout mavens. 

"And just like there are different shoes for different workouts, Monster is committed to a diverse lineup of iSport headphones that offer each user the type of experience he or she needs to achieve their best.

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