My son is currently somewhere between medium and large so we usually take the large and it's often baggy for him.
These (big ones) were very tight for him. Go at least one size bigger! Otherwise they appear to be reasonably well made and are likely to be comfortable.
👕 Brix Boys Long Sleeve Tees - Optimized Clothing for Boys
42 Review
Comfortable & Durable: Lucky & Me Noah 🩲 Boys Boxer Shorts 5 Pack - 100% Cotton Tagless Underwear
49 Review
🦖 HLMBB Dinosaur Toddler Underwear Training | Boys' Clothing for Easy Potty Training
44 Review
Pack of 6 Baby Soft Cotton Underwear for Little Boys - Dinosaur Briefs, Toddler Shark Undies, Children Truck Panties
41 Review
Boys' Adidas Active Sports Tricot Athletic Clothing
45 Review
Waterproof Cozy-Dry Rain/Snow Pants for 💧 Kids by JAN & JUL, with Fleece Lining
64 Review
Arctix Youth Pants Reinforced: Large Boys' Clothing for Active Adventures
46 Review
👕 Bold Pack Sleeve Active Hoodie Sweatshirt Set for Boys' Clothing - Stylish and Comfortable!
47 Review