The most common and most likely answer to this crossword clue is the 7 letter word SLEEVES
I've seen this crossword clue in The Guardian
S
L
E
E
V
E
S
Buddy explains!
The straight part
We know that "Records are put in these/parts of jackets" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case records are put in these/parts of jackets = sleeves.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SLEEVES mean?
SLEEVES noun- The part of a garment that covers the arm.
- A (usually tubular) covering or lining to protect a piece of machinery etc.
- A protective jacket or case, especially for a record, containing art and information about the contents; also the analogous leaflet found in a packaged CD.
- A tattoo covering the whole arm.
- A narrow channel of water.
- Sleave; untwisted thread.
- A serving of beer measuring between 14 and 16 ounces.
- A long, cylindrical plastic bag of cookies or crackers.
- A double tube of copper into which the ends of bare wires are pushed so that when the tube is twisted an electrical connection is made. The joint thus made is called a McIntire joint.
- To fit a sleeve to
- (magic tricks) To hide something up one's sleeve.