For all kinds of city and trekking tires you can find suitable tubes in Continental's range.

unitube	dimension	D	D40	A	A40	S42	S52	ETRTO	dimensions
Tour 26 slim	28/32 - 559/597		x			x		32 -559	26 x 1 1/8 x 1 1/2
								28, 32 -584	26 x 1 1/4 x 1 1/2
								32 -590	26 x 1 1/4 x 1 3/8
								32 -597	26 x 1 1/8 - 1 1/4 - 1,3
Tour 26	37/47 - 559/597		x		x	x		40, 44, 47 -559	26 x 1 1/4 - 1 3/8 - 1 5/8 - 1 1/2 - 1,6
								37, 40, 44, 47 -584	26 x 1 3/8 x 1 1/2 26 x 1,75 x 2
								32, 35, 37 -590	26 x 1,75 26 x 1 5/8 x 1 1/2
								32 -597	650A/B
Tour 28 slim	28/37 - 609-642		x	x		x		28, 32, 35, 37 -622	28 x 1 1/8 - 1 1/4 - 1 3/8 - 1 1/2 - 1,6
								28, 32 -630	28 x 1 3/8 x 1 5/8
									27 x 1 1/8 - 1 1/4 Fifty - 1 1/4
									700 x 28C, 32C, 35C, 37C
Tour 28 all	32/47-609/642		x		x	x	x	32,35,37 - 622	28 x 1 1/4 - 1 3/8 - 1 1/2 - 1,6
								40,42,44,47-622	28x1 3/8x1 5/8 28x1 5/8x1 1/2
								32-630	28x1,75x2
								40,44-635	27x1 1/4 Fifty -1 1/4
									700x38B,40B,42B
									700x32C,35C,37C,40C,47C

The advantages of the Continental Unitube system

• Multi-size tubes allow greater compatibility with more tire sizes, and fewer tubes.
• Unitubes are available in both Schrader and Presta valve tubes. Presta valves are available in a variety of lengths.
• All tubes are seamless and mold-cured (vulcanized) to ensure uniform roundness and improved reliability at the valve stem.
• Each and every tube passes a stringent 100% quality control inspection