Determining Overall Length for Your CoolSeat To determine the overall length of your seat, you will want to measure from the bottom edge of the shoulder strap openings, along the back of the seat, continuing on the seat portion (where your butt rests), to the leading edge of the crotch strap opening. See the images below for further clarification. The proper way to measure the overall length for your CoolSeat, from the bottom edge of the shoulder strap openings to the leading edge of the crotch strap opening.   This measurement starts too high on the seat back and ends too far forward on the seat. This measuerment will be too long, and your CoolSeat will not fit.   This measurement starts too low on the seat back and does not continue onto the seat portion. This measurement will be too short, and your CoolSeat will not fit.