How to send different Plan ID's to Stripe?

I worked through the Subscriptions with Stripe video and got everything working fine, with a single Plan ID.

Now I'm trying to modify it to work with multiple Plan ID's to give my users payment options.

I created a model to hold all of my plans, with each plan ID matching the plan ID at Stripe, so that I can pull the ID from params to send to Stripe.

The wall I've hit is that I can't seem to actually send the param ID to Stripe.

What am I doing wrong?

subscriptions_controller.rb

def create
    @company = Company.friendly.find(params[:company_id])
    @plan = Plan.find(params[:id]) ### This ID works on #show but can't be found in #create

    customer = Stripe::Customer.create(
        email: current_user.email,
        source:  params[:stripeToken],
    )

    subscription = customer.subscriptions.create(
        # plan: '001' ### This works
        plan: @plan ### This doesn't
    )

    @company.users.each do |user|
      user.update(
          subscribed_at: Time.now,
          canceled_at: nil
      )
    end

    current_user.update(
                    stripe_id: customer.id,
                    stripe_subscription_id: subscription.id,
                    card_last4: params[:card_last4],
                    card_exp_month: params[:card_exp_month],
                    card_exp_year: params[:card_exp_year],
                    card_type: params[:card_brand],
                    stripe_plan_id: @plan, ### Need this to work
                    invitation_limit: @plan.users ### Need this to work
    )

    redirect_to company_path(@company)

  rescue Stripe::CardError => e
    flash[:error] = e.message
    redirect_to company_upgrades_path(@company)
  end

Aren't you just missing .stripe_id or similar here plan: @plan ### This doesn't? Think the Stripe API wants a string here.

Just rewatched the video and realized Chris suggested hidden fields as the best solution for this. So I got it working by adding these hidden fields to my Stripe form:

<%= hidden_field_tag(:plan_id, @plan.id) %>
<%= hidden_field_tag(:plan_seats, @plan.seats) %>

And modifying my controller as such:

def create
    @company = Company.friendly.find(params[:company_id])
    @plan_id = params[:plan_id] # <<<<
    @plan_seats = params[:plan_seats] # <<<<

    customer = Stripe::Customer.create(
        email: current_user.email,
        source:  params[:stripeToken],
    )

    subscription = customer.subscriptions.create(
        plan: @plan_id # <<<<
    )

    @company.users.each do |user|
      user.update(
          subscribed_at: Time.now,
          canceled_at: nil
      )
    end

    current_user.update(
                    stripe_id: customer.id,
                    stripe_subscription_id: subscription.id,
                    card_last4: params[:card_last4],
                    card_exp_month: params[:card_exp_month],
                    card_exp_year: params[:card_exp_year],
                    card_type: params[:card_brand],
                    stripe_plan_id: @plan_id, # <<<<
                    invitation_limit: @plan_seats # <<<<
    )

    redirect_to company_path(@company)

  rescue Stripe::CardError => e
    flash[:error] = e.message
    redirect_to company_upgrades_path(@company)
  end