If your SP-375A vacuum loads from the canister's TOP you will be disappointed with this bag. It will fit and it's nice that a motor filter is included...BUT the bag will lose 1/2 it's capacity doing an immediate 90 degree turn. I have the SP-391A vacuum (45 years old) replaced the foot switch twice and a set of motor brushes but I have found that replacement bags need to have their in/out hole on the TOP...not on the END like this Eureka style 'B'. I'm going to keep looking for a better match to the Wards 'S' #82-973 vacuum bags.