ElasticCache cluster

[michgboxy2]

What is the difference between these two cluster-enabled connection methods?

const autoreselectionQueue = new Queue('auto-reselection', {
prefix: '{auto-reselection}',
host: '127.0.0.1',
port: 6739,
});

const instantShiftQueue = new Queue('auto-selection', process.env[process.env.REDIS_URL_ENV_NAME], {
prefix: '{autoselectQueue}',
createClient: () => new Redis.Cluster([{
host: '127.0.0.1',
port: 6739,
}]),
});

also, how can I replace the settings with Redis connection URL instead of host and port?