After experiencing 2 blowouts and doing some research, I want to let everyone know of an important safety item. Background: I purchased my PUP used from a friend. He owned it 7 years prior to selling to me. Never had any problems with the tires, no flats or anything. I had 2 blowouts in 2 separate trips. The tires were 7 years old (the spare as well). What I learned: My PUP is a Flagstaff 725D GVWR (Gross Vehicle Weight Rating) 3,095 lbs. Base/Dry Unit Weight 2,581 lbs. Base/Dry Hitch Weight 375 lbs. Base/Dry Axle Weight 2,206 lbs. Cargo Capacity 514 lbs. Box Size 12' Trailer Size (Closed) - Includes Hitch 17' 11" Height (Closed) 61" Trailer Length (Open) 23' 6" Interior Height (Open) 6' 6' Travel Width 85" Tire Size 13" R Power Converter with Charger 25 AMPS The important values are: GVWR (Gross Vehicle Weight Rating) 3,095 lbs. Base/Dry Unit Weight 2,581 lbs. Base/Dry Hitch Weight 375 lbs. Base/Dry Axle Weight 2,206 lbs. A gross vehicle weight rating (GVWR) is the maximum allowable total weight of a road vehicle or trailer when loaded - i.e including the weight of the vehicle itself plus fuel, passengers, cargo, and trailer tongue weight. Dry Weight is the empty weight of the vehicle or trailer. Dry weight may or may not include the weight of appliances, slide outs, etc. In this case, according to the manufacturer, these weights do not include any options such as A/C, HotWater Tank, refer, or heater. The manufacturer recommended ST 175/80R-13 tires. And in fact it came with 3 Carlysle tires of this size. These tires have a rating of 1360 meaning that each tire can support up to 1360 pounds for a total weight of 2760. If you do the math you will quickly see: (Trailer dry weight - tongue weight) / 2 (2581-375)/2=1103#'s or 81.1% maximum load of the tire. - Acceptable. (Trailer GVWR - tongue weight) /2 (3095-375)/2=1360#'s or 100% of maximum load of the tire. - Unacceptable. My trailer as weighed on local scales ((trailer weight with accessories and < 300 pounds of cargo. No water in tanks) - tongue weight)/2 (3380 - 400)/2=1490#'s or 109.5% of maximum load of the tire. - Very Unacceptable. After talking with the manufacturer (Flagstaff) after the second blowout and explaining the accessories included on the PUP I was assured that the tire I needed was ST 175/80R-13. I asked about putting a larger tire ST 185/80R-13 on since it had a higher load rating (1710*2=3420 or 87% of capacity) and was told that it may not fit on the slide out side. Why am I telling writing this? Before you purchase a PUP, you should insist on having the trailer weighed, as is, and include a fair estimate of cargo to ensure that the tires will support the load. Don't mean to hit you over the head, but this is a SAFETY issue.