sequelize confusion

var Service = sequelize.define('Service', {
	msisdn: {type: Sequelize.INTEGER}, 
	service: {type: Sequelize.STRING},
	correlationid: {type: Sequelize.STRING},
	supervision: {type: Sequelize.STRING},
	brand: {type: Sequelize.STRING}
});

var ChargeDetails = sequelize.define('ChargeDetails', {});

var Subscription = sequelize.define('Subscription', {
	subscriptionID: {type: Sequelize.INTEGER}, 
	subscriptionPhaseID: {type: Sequelize.INTEGER}, 
	chargeAmount: {type: Sequelize.INTEGER}
});

var ChargeBand = sequelize.define('ChargeBand', {
	vendorName: {type: Sequelize.STRING}
});

var ChargeBandIdentifier = sequelize.define('ChargeBandIdentifier', {
	chargeBandName: {type: Sequelize.STRING}, 
	chargeBandAmount: {type: Sequelize.INTEGER}
});

var SubscriptionType = sequelize.define('SubscriptionType', {
	subscriptionTypeName: {type: Sequelize.STRING}, 
	productCategory: {type: Sequelize.STRING}
});

ChargeDetails.belongsTo(ChargeBand);
ChargeDetails.belongsTo(Subscription);
Service.belongsTo(ChargeDetails);

ChargeBand.belongsTo(SubscriptionType);
ChargeBand.belongsTo(ChargeBandIdentifier);


SubscriptionType.sync({force: true});
ChargeBand.sync({force: true});
ChargeDetails.sync({force: true});
Subscription.sync({force: true});
ChargeBandIdentifier.sync({force: true});
Service.sync({force: true});