I'm pretty sure it's an ATL. At this price, it could definitely compete against a last-gen Viper V2 Pro. I honestly don't know much about Corsair mice, so here's an RTINGS review
About this item:
60gram – Ultra Lightweight for Quick, Precise FPS Play: Not just light. Ultra-light. Free of unneeded frills to achieve the lightest weight possible at 60gram, M75 AIR provides only what you need to win.
Ultra-Precise 26k DPI Optical Sensor: With a native 26,000 DPI, 650 IPS tracking, and up to 50G acceleration, the CORSAIR MARKSMAN optical sensor accurately captures fast-twitch mouse movements, speedy sweeps, and rapid recenters.
CORSAIR QUICKSTRIKE BUTTONS: CORSAIR QUICKSTRIKE delivers zero delay between the left and right click buttons and their switches, so your shots register instantly.
Fast Low-Latency Wireless: SLIPSTREAM WIRELESS offers a no-lag, sub-1ms connection. Alternatively connect via Bluetooth or USB to charge while you play.
Up to 100-Hour Wireless Battery with Fast Recharge: Keep winning for 100 hours via Bluetooth, round after round, on a single charge, and fully recharge in just 75 minutes or less.
Brilliant mouse and a great price! I have both this and the Viper ultimate, and there's very little to choose between the two. I find the M75's grip much more comfortable for long gaming sessions.