Pittsburgh Penguins blue liner Erik Karlsson could be a good fit for the Carolina Hurricanes, NHL insider Frank Seravalli believes.In an appearance on B/R Open Ice published on July 29, Seravalli delved into the question of the Carolina Hurricanes, currently valued at $1.25 billion by Forbes, adding Karlsson to their blue line.In his analysis, Servalli questioned how much value Karlsson would provide over current top blue liner, Shayne Gostisbehere. Servalli explained:“Let's say we can get our hands on Erik Karlsson, as he's got two years left on his deal at 10. Let's say we could get our hands on Erik Karlsson at seven and a half, which fits our cap situation, and still leave some flexibility moving forward.”Seravalli added:“How much better is Erik Karlsson at seven and a half than Shayne Gostisbehere, running your power play at a number much less than that? And I think that's the real curious question. Is there a gulf between the two? Probably.”The comparison between Karlsson and Gostisbehere stems from comparing both players’ cap hits. Karlsson’s current cap hit is $10 million for the next two seasons. Meanwhile, Gostisbehere’s cap hit is $3.2 million per season after signing a three-year, $9.6 million contract last summer.Under those circumstances, would the marginal value from adding Erik Karlsson justify the increased cap hit?Servalli doesn’t seem to think so. He questioned just how much better Karlsson would be than Gositsbehere, concluding that Karlsson’s age has played a key role in diminishing his overall value.Consequently, the Hurricanes might be better off utilizing their remaining cap space elsewhere this upcoming season.Erik Karlsson’s no-movement clause could complicate Penguins-Hurricanes tradeKarlsson's no-movement clause could make a Penguins-Hurricanes trade challenging - Source: ImagnErik Karlsson’s current contract contains a full no-movement clause, PuckPedia shows. That situation could complicate a trade moving forward. The Pittsburgh Penguins would need to get Karlsson’s approval before any trade could take place.That situation means that Karlsson controls his destiny. Even if the Penguins could find a team willing to take on Karlsson’s full cap hit for the next two seasons, Karlsson would still have to agree to the trade.Reports have suggested that Karlsson wants to play with a contending team. In that event, the Penguins' blue liner can nix any trade to a non-contending club. That’s why the Hurricanes seem like a perfect fit.The Hurricanes are one of the few contending teams that have enough cap space to add Karlsson’s contract.Moreover, Karlsson is under contract for two more seasons. That’s a situation that may encourage the Hurricanes to trade for Karlsson, as the deal wouldn’t represent a lengthy financial commitment.There’s no telling at this point if a trade between the Penguins and Hurricanes is imminent. But if it does happen, it would be the summer’s biggest deal.