Amazon Prime Big Deal Days are here, running October 6-7, and I've spotted a day-one discount on one of my favourite ever cycling products. The Magicshine SEEMEE 300 is 30% off, down to $41 from the usual $59.99. It's also the lowest US price I've ever seen, beating the previous best of $42.74, and given how popular the Magicshine is, it's unlikely to go much lower.Get the Magicshine SEEMEE 300 with 30% off this Amazon Prime Day.In the UK, the Magicshine is at a brilliant Prime Day price of just 35.52. That's not quite matching the 35.199 best-ever price, but it's only a few pence difference.UK shoppers can grab the Magicshine SEEMEE 300 with 15% off this Prime Day.The Magicshine SEEMEE 300 has topped our list as the best overall rear light in the best bike lights guide, but has recently dropped out and been replaced by the SEEMEE 400, which has a few extra tricks up its sleeve, including an extra 100 lumens and slightly longer battery life. However, it costs a lot more; currently, Amazon US has a not-very-impressive 7% off, down to $64.99 from $69.99, while Amazon UK has a better 20% off, down to 55 from 69.To access Amazon Prime deals, you'll need a Prime membership. You can sign up for a free 30-day trial and cancel anytime before the $14.99/8.99 per month fee kicks in.Magicshine SEEMEE 300 US deallowest ever priceSave 30%. The SEEMEE 300 was our best rear light overall, but is now superseded by its 400 sibling. However, the older model still has what it takes with a 200-hour runtime, and enhanced safety features include an in-built smart motion sensor that cleverly adjusts the brightness when you brake.View DealMagicshine SEEMEE 300 UK dealSave 15%. The Prime Day UK takes the 300-lumen output SEEMEE 300 rear bike light down to just 35. It features two LEDs that combine with a bonus downward-facing LED, which projects a beam directly onto the ground below you and massively increases your overall visibility.View DealTheres no doubt the SEEMEE 300 bike light packs a hefty punch, and I love it; it just wouldn't be an Amazon Prime Day shopping event without a decent discount to talk about.It's an outstanding bike light, and for this price vs the performance, theres no doubt it's one of the best bike lights I've ever owned.Although the Magicshine SEEMEE 400 has superseded it, the 300 is not to be underestimated, especially at this price. The battery run time is brilliant, with over 200 hours. That beats the 400 (107 hours) because it has a higher overall power output of 400 lumens.The superb battery life powers two LEDs, maxing out at 300 lumens, and the smart auto-dim feature also helps the battery last as long as possible by adjusting brightness to suit ambient light conditions. But the main feature I really like is the downward-facing LED, which projects a beam directly onto the ground below you, massively increasing visibility.