DEVLEC - In 1953, there were two different obverses used: the Shoulder Fold, and No Shoulder Fold. On circulated examples, many SFs appear to be NSFs, so it's easiest to identify using the letter I in ELIZABETH II DEI GRATIA REGINA. The NSF has flared I's, and the SF has straight I's.
There were also two different reverses used, some have the leaves (beside 5 CENTS) near the denticles, and some are further away. Looking at a few, you'll see the difference.
Most of the die pairings were either Shoulder Fold, Near Leaf, or No Shoulder Fold, Far Leaf. The other two combinations (Shoulder Fold, Far Leaf, and No Shoulder Fold, Near Leaf) are quite rare, and are sometimes dubbed mules (I personally disagree with the wording). As such, these varieties are worth a large premium (hundreds of dollars, rather than face value).