2C246 Lehman Heat Exchanger
Also Sendure 10337-1-5

For use with Lehman Engine
S-Super 185
P-Super 225
Super 160

2C273 and 2C273CN are the same part, both with a Copper Nickel bundle.
2c246, 2C269 and 2C269CN are all the same part. We ship them all with a CN bundle.

The 2c273 and the 2c246 / 2C269 look very similar but they are not interchangeable.
2C273 has two -1/8 hose fittings on the rear end cap
2C246 / 2C269 has one on end cap and one on side of shell. Both are 1-1/8.
Make sure you're ordering the right one.