What size tube for Trek Y3 Mountain Bike & what can I put in a biking gift basket?

I need to know what size tube goes to a Trek Y3 Mountain Bike so I can include some in a 'biking survival kit' i'm making my fiance for his birthday. I know the tube is a weird size because once he got one from walmart and the nipple thing was too big for his wheel.. Any help would be appreciated. Also, I'd love ideas from mountain bikers as to things I could put in the kit for him. I'm thinking a camel back, extra pedals, etc. Thanks!
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WOW! You have got to be the world's coolest fiance! Just a bit of terminology to make you sound even cooler. Tire tubes have valve stems. (There are nipples on bicycle wheels - spokes screw into them.) Anyhow, the kind of fat, rubber valve stem you see on a car is called a Schrader stem. The skinny, metal valve stem on some bikes is called "Presta." I am guessing he needs Presta stems and you probably won't tind them at Walmart. Your local bike store will have them, though. Try getting him 26x2.1, or so. (Anything close should do.) With winter coming on, your local bicycle shop should have a good collection of wool socks and long fingered cycling gloves to keep the extremities warm. As another respondent pointed out, a Crank Brothers Multi-Tools with chain tool is a great gift and you can never have too many. Also a derailluer hanger would stun any mountain biker with your thoughtfulness and anticipation of his needs. If he doesn't already have a closet of camelbacks, they are a great gift. Pedals rarely break so, I wouldn't bother with them. If you know his brand of pedals you can get some spare cleats, though. If he doesn't have a repair stand, they are costly, but make a great gift. A Park Tool race tool set falls in the expensive, but wonderful category, too. Food is always good. I love Lara Bars and Cliff's Shot Blocks. If his bike has V-Brakes or mechanical disk brakes a set of spare brake cables are good. Everyone needs a couple of spare derailluer cables, too. While you are at the bike store, buying cables, ask them for some metal cable ends. (Brake cables use a bigger cable end than derailleur cables, so ask for both.) BTW - When you explain your mission to the folks at the bike store, don't be surprised if you see their eyes well up with tears. Hope this helps you out and I hope you have a wonderful life.
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