[B00MER]

Edit skin1/customer/main/product.tpl and locate:

{if $config.Appearance.send_to_friend_enabled eq 'Y'}
<p />
{include file="customer/main/send_to_friend.tpl" }
{/if}
{if $active_modules.Detailed_Product_Images ne "" && ($config.Detailed_Product_Images.det_image_popup ne 'Y' || $js_enabled ne 'Y')}
<p />
{include file="modules/Detailed_Product_Images/product_images.tpl" }
{/if}
{if $active_modules.Upselling_Products ne ""}
<p />
{include file="modules/Upselling_Products/related_products.tpl" }
{/if}
{if $active_modules.Recommended_Products ne ""}
<p />
{include file="modules/Recommended_Products/recommends.tpl" }
{/if}
{if $active_modules.Customer_Reviews ne ""}
<p />
{include file="modules/Customer_Reviews/vote_reviews.tpl" }
{/if}

Replace with:

{include file="cartlab-tabs.tpl"}

The product.tpl file was modified slightly between 4.0 to 4.1 and may not match exactly but is basically the same jest.

hope this helps.