1 Search for the BELLOWS TYPE.
2 Search the BELLOWS NUMBER. The number is molded into the rubber part of the air spring.
3 Determine the material of the BOTTOM PLATE / PISTON TYPE.
4 Measure the TOP PLATE DIAMETER, making a note of the bolt pattern or taps (TOP PLATE HOLE / STUD QTY).
5 Measure the BOTTOM PLATE DIAMETER (or bottom bead plate), making a note of how the bolt pattern is oriented compared to the bolt of the top plate (BOTTOM PLATE ALIGNMENT) and, if applicable, making a note of the bolt pattern or taps (BOTTOM PLATE HOLE / STUD QTY).
6 Measure the height of the air spring (with no air pressure) from the top plate to the bottom piston. This is MAX HEIGHT. Compress the bag as far as possible with no air pressure and measure the height. This is the MIN HEIGHT.
7 Measure center to center of TOP bolts (TOP PLATE C TO C DIAMETER), and center to center of BOTTOM bolts (BOTTOM PLATE C TO C DIAMETER).
Additional information, if applicable, does it have a BUMPER and a BRACKET?