Here is a complete list of the level unlocks for Zwift cycling.
Level 1: Zwift Default Kit // 0 XP
Level 2: Zwift Basic Kit // 1000 XP
Level 3: Zwift Helmet Part Deux // 2000 XP
Level 4: Zwift Glasses #1 // 3000 XP
Level 5: Black Shoes // 4000 XP
Level 6: Gloves // 5000 XP
Level 7: Solid Socks // 7000 XP
Level 8: Vintage Kit Pack // 10,000 XP
Level 9: Camo Jersey Pack // 13,000 XP
Level 10: Zwift Glasses #2 – Oakley // 16,000 XP
Level 11: Digital Camo Kits // 19,000 XP
Level 12: Basic Kit 2 // 23,000 XP
Level 13: Dotted Socks // 28,000 XP
Level 14: Pattern Gloves // 33,000 XP
Level 15: Level 15 Jersey // 38,000 XP
Level 16: Zwift Glasses #3 // 44,000 XP
Level 17: Striped Socks // 50,000 XP
Level 18: Classy Kits // 56,000 XP
Level 19: Zwift Glasses #2 // 62,000 XP
Level 20: Level 20 Jersey // 70,000 XP
Level 21: Flouro Kits // 78,000 XP
Level 22: Patterned Socks // 88,000 XP
Level 23: Solid Gloves // 94,000 XP
Level 24: Skate Helmet // 100,000 XP
Level 25: Level 25 Kit // 110,000 XP
Level 26: Oversize Glasses // 121,000 XP
Level 27: White S-Works Shoes // 130,000 XP
Level 28: Dotted Socks // 140,000 XP
Level 29: S-Works Helmet(Evade) // 150,000 XP
Level 30: Level 30 Kit // 170,000 XP
Level 31: Zwift Oakley Eyeshades // 180,000 XP
Level 32: Newsy Cap/Hat // 190,000 XP
Level 33: Fluoro Gloves & Limar Air Speed Helmet // 200,000 XP
Level 34: Monochrome Kit // 220,000 XP
Level 35: Mavic Shoes(Yellow) // 230,000 XP
Level 36: Food Themed Socks // 250,000 XP
Level 37: Bell Javelin Helmet(Insanely aero helmet) // 260,000 XP
Level 38: Vintage Gloves // 260,000 XP
Level 39: Leather Shoes // 290,000 XP
Level 40: Level 40 Kit // 310,000 XP
Level 41: Rockstar Glasses // 330,000 XP
Level 42: La Z Claire Kit // 340,000 XP
Level 43: 80s Helmet // 360,000 XP
Level 44: Alpine Slopes Kits // 380,000 XP
Level 45: Giro Synthe Helmet // 400,000 XP
Level 46: Prism Kits // 420,000 XP
Level 47: Vintage Goggles // 440,000 XP
Level 48: Bontrager Shoes // 460,000 XP
Level 49: Giro Vanquish Helmet // 480,000 XP
Level 50: Level 50 Kit // 500,000 XP