Both are Physio-Control AEDs, but they target different buyers. The LIFEPAK 1000 is a professional responder AED designed for BLS and ALS providers (fire, EMS, law enforcement, athletic trainers). It delivers up to 360 J, supports 3-lead ECG and manual override on the Graphical Display variant, uses QUIK-COMBO REDI-PAK pads that are interchangeable with LIFEPAK 15 and 20e monitors, carries a 5-year warranty, and weighs 7.1 lbs. The LIFEPAK CR2 is a lay-rescuer public-access AED designed for workplaces, schools, and homes. It uses RHYTHMx electrodes (not QUIK-COMBO), provides CPR coaching via cprINSIGHT analysis, carries an 8-year warranty, and weighs 4.4 lbs. Choose the LIFEPAK 1000 for trained-responder deployments; choose the CR2 for public-access programs.