Good to know- The QP410 blade has a glide coating and rounded tips that cut hair closely, leaving you with a smooth finish- Combining a fast-moving cutter with a dual protection system, the blades are efficient and comfortable- You can get to tricky spots more easily with the 360 blade that moves in all directions- They're IPX7 waterproof, so you can choose between a shave with or without foam- You can use this replacement blade with most OneBlade handles, and it'll last you around 4 months______________________________________________________________Please note: Fits with all OneBlade products: OneBlade (QP25xx, QP26xx, QP27XX, QP28XX), OneBlade Pro (QP6504, QP653x, QP654x, QP665x) except for QP1XXX, QI1XXX, QP652x, QP651x, QP662x, QP6505.